AMNIOTIC MEMBRANE A TEMPORARY SOLUTION IN ... en.pdfANNUAL CONGRESS OF THE ROMANIAN CONTACT LENS...

ANNUAL CONGRESS OF THE ROMANIAN CONTACT LENS ASSOCIATION

AMT, vol II, nr. 1, 2010, pag. 45

AMNIOTIC MEMBRANE – A TEMPORARY SOLUTION

IN CASE OF PERFORATED CORNEAL ULCER

CRISTINA NICULA1, D. NICULA2, M. BLIDARU3, LAURA STĂNILĂ4,

SIMINA MUREŞAN5

1,2,4 Optilens Clinic Cluj-Napoca, 3,5 UMF Cluj-Napoca

Abstract: We present the case of a female patient, 30

years old, who developed a perforated corneal ulcer at

which we made an amniotic membrane graft as a

temporary solution in order to save the eye

Keywords: amniotic membrane, corneal ulcer

Rezumat: Se prezintă cazul unei paciente cu ulcer

cornean perforat, la care s-a efectuat un transplant de

membrană amniotică, ca soluţie temporară pentru

salvarea globului ocular.

Cuvinte cheie: membrana amniotica, ulcer cornean

INTRODUCTION

In 1940, Roth [7] was the first who used

amniotic membrane for ophthalmic purpose.

Tseng and col. [9,10] have done recent

transplantation of amniotic membrane for the

management of patients with corneal defects.

The indications for amniotic membrane graft are:

persistent epithelial defects, progressive corneal ulcer,

painful pseudophakic keratopathy, corneal neurotrophic

alteration, simblepharon, conjunctival melanoma, bolouse

epidermolisis (children) [3,4,5,6,8]. The amniotic

membrane can also be used, but with minimal efficiency

in: stem cell deficiency, Steven-Johnson syndrome,

trachoma, ocular pemfigoid [1]. In this cases it is

associated with limbal stem cells graft.

The clinical properties of amniotic membrane

are: facilitates corneal epitelisation (migration and

adhesion of epithelial cells), conservation of functional

limbal cell stem, decrease of inflamation (citokinases,

proteases inhibitors), decrease of scarring process,

diminish neovascularisation [2].

PURPOSE

The purpose of the paper is to established the

efficiency of amniotic membrane in a case of perforated

corneal ulcer.

History

The paper presents the case of a 30 years old

female, who had a surgical intervention for a right

acustico-vestibular neurinoma, two years ago. After the

surgery she remained with a peripheral facial paralyses

and lagophtalmy on the right eye. In time she developed a

neuroparalitical keratites, having local treatment with

nonsteroidical drugs (Indocolir 3x/zi), artificial tears

(Systane 2x/zi) and epitelisation drugs (Corneregel 2x/zi).

The patient refuses the blepharoraphy and according with

her mother’s indication she instilated in this eye a drog

called Tataneasa tincture. Immediately after the

instillation she accuses intensive ocular pain, epiphora

and blepharospasm. At the slit lamp examination we

discovered a central corneal ulceration, very large, which

retained the dye. We recommended continuing the local

treatment with epitelisation drugs, artificial tears,

nonsteroidical drugs and ocular patch. Unfortunately the

evolution was to descemetocel and corneal perforation.

Reasons for ophthalmologic consultation

These reasons consists of: worm liquid on the

face, ocular pain and blepharospasm, symptoms and signs

present at right eye.

Pathological personal data

We retain the operation for the acustico-

vestibular neurinoma, followed by facial paralyses.

Ocular exam revealed

RVA = PSL

LVA = 1

Ocular refraction: RE – cannot be done, LE - + 0,5

Slit lamp examination

o RE:

- mixed conjuntival congestion;

- the cornea is hypotransparent with a

central corneal perforation, about 2mm,

with inclavated iris at this level,

surrounded with corneal edema;

- anterior chamber is absent, the iris

being pushed to the corneal

endothelium

o LE: normal anterior segment;

Ocular fundus:

o RE – cannot be seen;

o LE – normal.

Positive diagnosis

On the base of the history and ocular exam we

put the diagnosis of: RE: Lagophtalmy. Perforated corneal

ulcer. Exogenous acute uveitis.

Evolution

In the absence of a correct and urgent treatment

the evolution of the case is to endophtalmitis,

panophtalmitis and functional and anatomical loss of the

eye.


AMT, vol II, nr. 1, 2010, pag. 46

Treatment

In this case the treatment has to be done urgent

and follows the obturation of the corneal perforation.

Because of the lack of the possibilities to make the

corneal graft the single modality to maintain the eye is the

amniotic membrane graft.

We made the prelevation of amniotic membrane

from a female placenta operated by caesarian delivery

with HIV, HVB, HVC, syphilis tests negative. We also

made the separation of amniotic membrane by dissection

after washing with cephalosporin and stored in sterile

conditions.

The surgery technique consists of:

- topic anesthesia with Benoxinat;

- introduction of viscoelastic substance at the level of

perforation, in order to push backward the iris (fig.

1);

- perilimbal conjunctive incision (fig. 2);

- placement of amniotic membrane with the epithelial

face upward on the cornea (fig. 3);

- inseration of amniotic membrane under the bulbar

conjunctiva (fig. 4);

- surget suture of the amniotic membrane to the

conjunctiva with Vycril 7.0 (fig. 5);

- placement of a therapeutically contact lens;

- ocular bandage till the following day.

Figure no. 1. Viscoelastic substance injection in the

corneal perforation

Figure no. 2. Perilimbal conjunctival incision

Figure no. 3. Placement of the amniotic membrane

Figure no. 4. Insertion of amniotic membrane under

the conjunctiva

Figure no. 5. Suture of the amniotic membrane to the

conjunctiva

Postoperative treatment consist of instillation of

Floxal 0,3% - 3x/day, in association with Flumetol –

3x/day and Systane – 2x/day.

The evolution was favorable. In the first day after

the surgery the patient didn’t have any ocular pain, the

amniotic membrane was on the place and the anterior

chamber was small but present.

The follow up was made at 48-72h and than at

every 3 days for a period of 2 month. After 3 weeks we

saw the complete resorbtion of the amniotic membrane,

with the total epitelisation of the corneal ulcer and the

stabilization of the cornea, without inflammation. After 6

weeks, appeared a central corneal scar with a normal

anterior chamber.

After one year the patient had a corneal graft in

Budapest and a implantation of a golden platelet in the

superior eyelid in order to diminish the lagophthalmy.

Prognosis

The visual prognosis of the patient is strictly

dependent on the presence of lagophthalmy which was

not solved completely and can influence the corneal graft

statement.

Case particularities

The unfavorable evolution of the case to corneal

ulcer and perforation was determined by the lack of

blepharophy at the certain moment and the association of

local medication of the patient, which represented the

trigger.

CONCLUSIONS Amniotic membrane transplantation is a

temporary solution in tectonic correction of corneal or

conjunctival defects


AMT, vol II, nr. 1, 2010, pag. 47

BIBLIOGRAPHY 1. Di Pascuale MA, Espana EM, Liu DT, Kawakita T,

Li W et all. Correlation of corneal complications

with eyelid cicatricial pathologies in patients with

Steven-Johnson syndrome and toxic epidermal

necrolysis syndrome. Ophthalmology 2005;

112:904-912.

2. Gabric N, Mravicic I, Dekaris I, Karaman Z,

Mitrovic S. Human amniotic membrane in the

reconstruction of the ocular surface. Doc

Ophthalmol. 1999; 98:273-283.

3. John T, Foulks GN, John ME, Cheng K, Hu D.

Amniotic membrane in the surgical management of

acute toxic epidermal necrolysis. Ophthalmology

2002; 109:351-360.

4. Pires RTF, Tseng SCG, Prabhasawat P,

Puangsricharern V, Maskin SL, Kim JC, Tan DTH.

Amniotic membrane transplantation for

symptomatic bullous keratopathy. Arch.

Ophthalmol., 1999; 117:1291-1297.

5. Prabhasawat P, Tesavibul N et all. Efficacy of

amniotic membrame patching for acute chemical

and thermal ocular burns. J.Med.Assoc.Thai. 2007;

90:319-326.

6. Prabhasawat P, Tesavibul N, Komolsuradej W.

Single and multilayer amniotic membrane

transplantation for persistent corneal epithelial

defect with and without stromal thinning and

perforation. Br.J.Ophthalmol., 2001; 85:1455-1463.

7. Roth A. Plastic repair of conjunctival defects with

fetal membrane. Arch. Ophthalmol., 1940, 23:522-

525.

8. Tejwani S, Kolari RS, Sangwan VS, Rao GN. Role

of amniotic membrane graft for ocular chemical and

thermal injuries. Cornea 2007; 26:21-26.

9. Tseng SCG, Espana EM, Kawakita T, Di Pascuale

MA, et. all. How does amniotic membrane work?

The ocular surface 2004; 2:177-187.

10. Tseng SCG, Prabhasawat P, Barton K, Gray T,

Meller D. Amniotic membrane transplantation with

or without limbal allografts for corneal surface

reconstruction in patients with limbal stem cell

deficiency. Arch. Ophthalmol., 1998; 116:431-441.


AMT, vol II, nr. 1, 2010, pag. 48

CONTROVERSIES BETWEEN TORIC AND RIGID

CONTACT LENSES FOR HIGH ASTIGMATISM

CORRECTION

CATALINA CORBU1 MIHAELA CONSTANTIN2

1 Oftaclinic Bucharest, 2 Emergency Hospital of Ophthalmology, Bucharest

Abstract: The paper presents theoretical aspects

concerning the astigmatism like cause, classification,

correction by toric and rigid contact lenses. Advantages,

disadvantage and practical aspects of these lenses use for

correction of high astigmatism are discussed.

Keywords: toric contact lenses, rigid contact lenses,

astigmatism

Rezumat: Lucrarea prezinta aspecte teoretice privind

astigmatismul – cauze, clasificare, corectie prin lentile de

contact torice si dure. Sint discutate avantajele,

dezavantajele si aspecte practice ale folosirii acestor

tipuri de lentile in corectia astigmatismelor mari.

Cuvinte cheie: astigmatism, lentile de contact moi, lentile

rigide

INTRODUCERE

The astigmatism represents a refraction disorder

in which the light comes parallel from the infinite focus in

many regular or irregular points after passing ocular

diopter. Regular astigmatism presents an orderly

geometrical deviation, has the principal meridians 90

degrees apart and is corrected with spectacles. Irregular

astigmatism presents an disorderly deviation, the principal

meridians are not 90 degrees apart and this astigmatism

cannot be completely corrected with soft toric lenses.

Isac Newton described the astigmatism in 1670

for first date.

Total astigmatism represents the sum of anterior

corneal astigmatism and intern astigmatism. Intern

astigmatism is the sum of posterior corneal astigmatism,

lens astigmatism, retinal astigmatism and optical

aberrations. High astigmatism has a value higher to 2.50D

and can corrected with toric soft contact lenses or rigid

contact lenses. The table shows the patients distribution

with astigmatism which want wearing contact lenses. We

observe that almost 10% from patients have astigmatism

higher 2.50D.

Holden study shows that 25% patients have an

astigmatism <0.25D and 10% patients which need

correction have an astigmatism > 2.75D. The same study

showed that the astigmatism evolutes during life:

- the percent of with – the - rule astigmatism decrease

from 75% in the first decade to 20% at fifth decade.

- the percent of against the rule astigmatism increase

from 20% in the first years to 65% at 50 years old.

- the percent of oblique astigmatism represent 20% -

25% and is invariably during life.

Astigmatism value Percentage

> 0.25 D 76.5%

> 0.50 D 61.5%

> 0.75 D 45.4%

> 1 D 34.8%

> 1.25 D 24.8%

> 1.50 D 19.2%

> 1.75 D 15.8%

> 2.25 D 10%

> 2.75 D 6%

> 3 D 3.4%

These changes are determinate by: decrease

corneal base curvature on main meridians, the horizontal

base curvature is almost equal with the vertical base

curvature; the physiological astigmatism disappear during

life; the palpebral pressure decreases on vertical meridian

– with age the collagen structure changes the rigidity and

favors change with – the- rule astigmatism in against the

rule astigmatism.

Correction of irregular astigmatism is different in

function of Amsler classification:

- Stadium I is characterized by oblique astigmatism

and is corrected with spectacles or soft contact lenses.

- Stadium II is characterized by high irregular

astigmatism and is corrected with rigid contact

lenses.

- Stadium III is characterized by almost impossible

recorded astigmatism and sometimes is corrected

with rigid contact lenses.

- Stadium IV the astigmatism is impossible recorded,

corneal opacities need correction with rigid contact

lenses and/or piggyback, or are not corrected.

Correction of astigmatism with soft and rigid

contact lenses founds two new interfaces one between the

air and the anterior surface of lens and other between the

posterior surface lens and the anterior surface of tear film.

The correction of total astigmatism with contact lens


AMT, vol II, nr. 1, 2010, pag. 49

needs a good static and dynamic centration of contact lens

without rotation on the cornea.

Correction of cornean astigmatism or mixt

astigmatism is perform with soft posterior toric lens.

Intern astigmatism is correct with anterior or posterior

toric lens.

Soft toric contact lens is indicating for:

- astigmatism higher 1D

- intolerance at rigid contact lens

- improper correction of visual acuity with soft

spherical contact lens

- raport sphere/cylinder <4/1.

The using toric contact lens for the correction of

astigmatism has the following advantages: comfort –

frequently is the first option for patient (studies and

practices show that rigid contact lenses have the similar

comfort too, after the patients were accommodated); the

stability is influenced by hydrostatic, gravitational and

palpebral forces, the superior side is cover by superior lid

and with blinking the lid slips on contact lens without its

dislocation; visual acuity is high; is possible the wearing

for long time with maintain optical stability at blinking

time; these contact lenses have a less influence for corneal

metabolism with better tolerance; ocular injuries is rarely.

Disadvantages are represented by: fragility, short

time for use, difficulties in correction of high

astigmatism; hardly cleaning and desinfection with

destroyer of lens; deposits on the lens (mucus, proteins);

infection risk (fungi’s, bacterial contamination) anything

lesion at level of contact lens creates adherents situs for

potential microorganism; “perfidies” lenses with a high

rate ischemic or infection complications in defections

using (wearing use, hygiene, ophthalmologic control);

they can determine visual acuity disorder even in

perfectly fitting, due to dehydratation of lens, the

astigmatism or the lens deposits.

Rigid contact lens gas permeable (RGPCL)

apparition marked an important step in evolution of

contact lenses by satisfactory contribution for corneal

oxygen permeability permitting a normal corneal

metabolism and decrease intolerance injures with corneal

edema. There are spherical, toric and bitoric RGP.

Anterior toric RGP contact lens corrects intern or mixt

astigmatism. For residual astigmatism can be use bitoric

RGP contact lens. Corneal astigmatism is corrected with

spherical RGP contact lens and residual astigmatim is

corrected by anterior toric RGP lens.

Rigid contact lens is use for:

- correction almost 90% anterior corneal astigmatism

- correction of astigmatism higher 3 D, uncorrected

with soft toric lenses

- correction of irregular astigmatism

- patients with giant-papillary conjunctivitis,

precarious hygiene.

Advantages for using RGP contact lenses are

represented by:

- better correction for astigmatism so we have a better

optic quality than soft toric lenses (patients with

astigmatism higher 1D have a less visual acuity by

correction with soft lenses because these lenses

adhere on corneal toric surface)

- higher and stable visual performance

- the flux of tears is permit under contact lenses and at

patients with sicca syndrome maintain hydrofoils

state

- durability

- easy maintenance.

Disadvantages are representing by: long time for

adaptation, shorter time of tolerance, optical instability in

blinking time, easy dislocation, higher risk for loosing,

frequently blinking, palpebral ptosis, ocular irritation. For

irregular astigmatism, sometimes unrecorded, with K

medium >60D is indicating to use piggyback technique

which has the following advantages:

- better comfort

- good centration

- lower loosing risk

- protection for the apex.

Disadvantages of this technique are representing

by manipulation and maintenance for two lenses and

higher price.

We present six cases with high astigmatism

corrected with contact lens.

Case I:

Male patient, 25 years old with refraction RE : -

3.25 sph <> -3.75 cyl ax 42. UCVA for RE is 0.3. BCVA

for RE with toric lens is 0.7 with -2.25 cyl ax 40 and by

RGP contact lens (7.5/-2.25/9.85) is 10/10.

Case 2: Male patient, 17 years old, with refraction at RE:

-2.25 sph <> -3.50 cyl ax 15. UCVA RE is 0.05. BCVA

RE is 1.0 with toric lens -2.50 sf <> -2.25 cyl ax 10

Case 3:

Male patient with keratoconus, 21 years old with

refraction at LE: -1.50 sph <> -8.50 cyl ax 158. UCVA

LE is 0.1. BCVA LE is 0.7 with RGP contact lens 7.6/-

3/10.0

Case 4:

Male patient with keratoconus has refraction at

RE: -4.50sph <> -9.50 cyl ax 14 and LE: -2.25 spf <> -

8.50 cyl ax 165 UCVA RE is 0.05. BCVA RE is 0.8 with

RGP 7.1/-6.50/10.0. UCVA LE is 0.1 BCVA LE is 1 with

RGP 7.4/-3/10.0

Case 5:

Male patient 17 years old with refraction at RE:

+3.25 sph <> -5 cyl ax 23.

UCVA RE is 0.05.

BCVA RE is 0.5 with toric lens -2.25 cyl ax 20;

uncorrected with RGP contact lens.

Case 6:

Female patients, 16 years old has refraction at

RE: +4 sph <> -4 cyl ax 18. UCVA RE is 0.1 BCVA with

toric lens +1 sph<> -1.75 cyl ax 20 is 0.6; uncorrected

with RGP contact lens.

CONCLUSIONS

Soft toric and rigid contact lenses are a solution

for correction high astigmatism, the option of patient has


AMT, vol II, nr. 1, 2010, pag. 50

been major importance in choosing.

Rigid gas permeable contact lenses are preferred

physiologic for long wearing fitting by high

transmissibility of oxygen. Improvement of visual acuity

with this kind of lens for patient with keratoconus is an

evidence of diagnosis confirmation.

Correction of astigmatism with soft toric lens is

easier, but these must have higher oxygen permeability

and frequently there change. In cases with hyperopia

refraction, visual acuity is correct with toric contact lens.

BIBLIOGRAPHY 1. Chaudhry M., Contact Lens Primer 2007

2. Pavan Langston D., Manual of ocular Diagnosis and

Therapy 2002, 398-430.

3. Malet F., Les Lentilles de contact 2009, 373 – 461.


AMT, vol II, nr. 1, 2010, pag. 51

THE CROSS – LINKING TECHNIQUE IN CORNEAL

PATHOLOGY

CRISTINA NICULA

Optilens Clinic Cluj-Napoca

Abstract: Cross – Linking (CXL) is a photopolimerization

of the stromal fibrillas, in order to increase their stiffness

and resistance to the keratectasia, through the combined

action of a photosensitizing substance (riboflavin and

Vitamin B2) with the irradiation of ultraviolet light

performed with an illuminator in a solid state of UVA

kind (18). The main objective is to slow down or arrest

the progression of keratoconus, avoiding, or at least

delaying the necessity of keratoplasty.

Keywords: cross-linking, keratoconus

Rezumat: Cross – Linking (CXL) este un proces de

fotopolimerizare al fibrelor stromale corneene, în vederea

creşterii rezistenţei şi rigidităţii corneene, prin acţiunea

combinată a substanţei fotopolimerizante – riboflavina -

şi a radiaţiei ultraviolete eliberată de un aparat special -

CMB X LINKER (18). Obiectivul tehnicii de cross-linking

a fost de a încetini sau stopa progresia keratoconusului,

astfel evitând sau cel puţin întârziind necesitatea

transplantului corneean.

Cuvinte cheie: cross-linking, keratoconus

Definition

Cross – Linking (CXL) is a photopolimerization

of the stromal fibrillas, in order to increase their stiffness

and resistance to the keratectasia, through the combined

action of a photosensitizing substance (riboflavin and

Vitamin B2) with the irradiation of ultraviolet light

performed with an illuminator in a solid state of UVA

kind (18).

History of Cross – Linking

CXL was developped from 1993 till 1997 by

Gregor Wollensak, Theo Seiler and Eberhard Spoerl

(University of Dresden, Germany) (19). First patients

treated in 1998.

Objective of Cross – Linking The main objective is to slow down or arrest the

progression of keratoconus, avoiding, or at least delaying

the necessity of keratoplasty.

The rationale of the procedure is supported by

the fact that very few young diabetic patients are affected

by keratoconus (17).

In the rarest of occasions, pre-existing

development of keratoconus before the onset of diabetes

does not show any progression due to the natural cross-

linking effect of glucose (chemical cross-linking) (21).

The principle of Cross – Linking Photopolymerization using the UV-light was

found to be the most promising technique to achieve

cross-links in connective tissue.

Photopolymerization is activated by means of a

non-toxic and soluble photomediator and a wavelenght

which is absorbed strongly enough to protect deeper

layers of the eye (riboflavin) (3).

Mechanism of Cross – Linking

UV-A radiation with administration of riboflavin

– dextran solution as a photosensitizer, represent the

trigger of the mechanism. After the combining action

singlet oxygen and superoxide free radicals are liberated

and the physical CXL of the corneal collagen fibers is

done.

Intrahelical and interhelical cross-links can be

formed within or between the tropocollagen units that

comprise the individual collagen fibrils.

Intermicrofibrillar cross-links can form between adjacent

collagen microfibrils that comprise the collagen lamellae.

This goes to slow down of thinning and increase strenght

of cornea (25).

Biomechanical changes in the cornea after Cross –

Linking

Andreasson and col. (2) showed in their studies

that the biomechanical strenght of the cornea is

abnormally low in keratoconus. Elsheikh and Hadley and

Krueger and Seiler (7,8,12,17) have demonstrated that

keratoconus rarely occurs in instances where corneal

stiffening is increased by enhanced collagen CXL

(elderly, diabetes).

The basis of enhanced biomechanical strength in

cornea after CXL consist of the formation of covalent

cross-links and interaction of free radicals with

aminoacids in neighbouring collagen molecules after the

combined action of the photosensitizer : riboflavin

applied on the desepithelized surface of the cornea and

exposure to UV-A light (25).

It was not yet demonstrated if the cross-links are

confined to collagen or they occur nonspecifically in

tissue.

Theoretically the collagen fibers surfaces are too

widely separated to allow direct interfibrillar linkages.

Corneal collagen associates with other bridging collagens


AMT, vol II, nr. 1, 2010, pag. 52

and proteoglycan molecules which determine indirect

interfibrillar cross-linking via these molecules (26).

Müller and col. (15) showed in a study made on

sheep cornea that cross-linked corneas swell less than

normal. Their results were that riboflavin – dextran

reduce the sheep corneal thickness up to 17% in 35

minutes of exposure. They couldn’t explain if the

resistance to stromal swelling in CXL – treated corneas is

due to presence of dextran or indirect interfibrillar CXL.

Wollensak and col. (25) demonstrated that CXL

halts the progression of keratoconus and even a slight

regression. Braun and col. (3) studied the corneal rigidity

after CXL, showing that there is a decrease in corneal

elasticity after riboflavin / UVA CXL (contact ultrasonic

device). Luce and col. (13) established that corneal

hysteresis is an indicator of corneal viscoelasticity

(Ocular Response Analyzer). Albe (1) and Zadok (26)

demonstrated in their studies in ovine cornea that CXL

increases corneal hysteresis. In the same time it was

shown that biomechanical measurements may be

influenced by changes in parameters during CXL

(thickness + hydration).

Spoerl and col. (19) measured the biomechanical

stress – strain from cross-linked corneas. Other authors

(22,23) showed stiffening following treatment and

increase in corneal rigidity with 320% in humans.

In long term follow up the stiffening effect is

maintained over 8 months (22,24). In time long term

durability of the strengthening effect appeared (24).

Advantages of Cross – Linking

The advantages of Cross – Linking are: easy to

perform, noticeably reduced time of procedure, localized-

selective treatment, lack of scarring, availability of

riboflavin, non-toxic and hydrosoluble, good stromal

penetration. Cross – Linking technique is safe. Riboflavin

can decrease of about 95% the UVA light intensity,

allowing to remain below the endothelium citotoxic

threshold for corneal thickness > 440 micron (<0.36

mW/cm2).The riboflavin role consist of: absorption and

concentration of the UV radiation, is the

photosensibilizing agent for the production of a kind of

reactive oxygen and gives endothelial protection. The

riboflavin 0.1% solution contains dextran T500 20%

which maintains the osmolarity, avoiding corneal soaking

and swelling during the treatment.

Known risks of Cross – Linking The Cross – Linking technique gave no side

effects for the corneal endothelium, lens and retina. Post

surgery the patient complained of pain and feeling of

foreign body for 24 – 48 hours, till reepitelization is

complete and hyper-tearing for 24-72 hours. Transitory

corneal edema with visual haze for 30 – 60 days was seen.

The treatment does not exclude the possibility of

keratoplasty.

Does Cross – Linking promote artificial aging ?

CXL increases corneal stiffness and resistance to

enzymatic digestion (18,20). In the same time CXL alters

cornea’s behavior under thermal, hydrostatic and

electrophoretic stress (20), but the exact magnitude of its

clinical effects cannot be quantified.

Marshall and col. (14) studied 9 corneas who

underwent epithelial debridement alone. Other corneas

had epithelial debridement and CXL and others epithelial

debridement and CXL with glutaraldehide 10%. The

results showed the increase in corneal stiffness linear with

age. The corneal young’s modules increased 4,3 times so

that CXL ages the cornea 600 years in aprox. 600

seconds.

Types of Cross-Linking There are 4 types of Cross-Linking:

1. Enzymatic Cross-Linking (the natural collagen

Cross-Linking)

2. Chemical Cross-Linking (glutaraldehyde,

formaldehyde)

3. Photochemical Cross-Linking (UVA rays, ionizing

radiations)

4. Photooxidative Cross-Linking (riboflavin-UVA)

Indications of Cross-Linking:

1. keratoconus:

- progressive keratoconus in younger patients,

patients with early diagnosis or slightly older

patients showing refractive instability (increasing

astigmatism or myopia – topographical analises);

- established keratoconus and intolerance of hard

contact lenses (CXL improve the shape of cornea

for better contact fitting)(4);

- recurrent keratoconus after penetrating keratoplasty

( 24);

2. pellucid marginal degeneration;

3. post LASIK ectasia (4) ;

4. bullous keratoplasty (16);

5. corneal melting and ulcers (5);

6. pathologic myopia (10,11).

Contraindications of Cross-Linking:

1. corneal pachymetry under 400 µm;

2. central corneal scars;

3. Vogt striae;

4. epithelial healing disorders such as map dot

dystrophy and rheumatism disorders;

5. refractive radial keratotomy;

6. previous herpes simplex virus keratitis (UV-A may

induce herpes reactivation);

7. pregnancy.

Ocular examination before Cross-Linking:

The ocular examination before Cross-Linking

starts with the discussion with the patient about CXL

(Preoperative Councelling). It has to give the following

information to the patient :

- the goal of CXL is not a refractive endpoint;

- additional chair time and patience;

- explain the technique, its effects (limits further

progression);

- spectacles or CL still be required;

- can continue their lifestyle + jobs;

- postoperative course (haze, pain, delay in

epithelisation, infection, sterile infiltrates, tear

dysfunction);

- RGP – removed 2 weeks before CXL;


AMT, vol II, nr. 1, 2010, pag. 53

- vit.C (antioxidant) – discontinued 1 week before

CXL in patients with atopic eye disorders or poor tear

function;

- the effect of CXL – may take 3 - 6 months;

- note a slightly loss of BCVA.

The ocular examination consists of:

- UCVA, BCVA;

- ocular refraction;

- keratometry (must be less than 60D);

- corneal topography (Pentacam);

- pachymetry (at least 400 µ);

- counting of endothelial cells

Technique of Cross-Linking:

a. The standard protocol:

- sterile opening in the surgery room of the ophthalmic

solution of riboflavin 0,1% - dextran 20%;

- verification of the power of the illuminator UVA

array in a solid state CBMX linker with a UVA

power meter;

- topical anesthesia (alcaine) – 3-4 drops, 15-20min

before CCL;

- removal of the corneal epithelium 9mm of diameter;

- instillation of a drop of alcaine;

- instillation of riboflavine 0,1% every 3 min for 30min

before the irradiation;

- corneal irradiation of central 9mm through the

CMBX linker + instillation of riboflavine 0,1% every

3min – 30min;

- instillation of ofloxacin + indocolyre;

- TCL for 3-4 days

b. The modified protocol:

b1. In thin corneas (advanced progressive keratectasia)

In this protocol is used the hypoosmolar

riboflavine solution 0,1% (9) (does not contain dextran).

After the removal of the epithelium it is instillated this

solution till the width of cornea is 400 µm. After that the

technique is similar as in the standard protocol.

b2. Transepithelial tensioactive mediated Cross-Linking

(Protocol of Roberto Pinelli).

In this protocol is used the riboflavine that

contains benzalkonium chloride (BAK). The solution is

applied directly onto the intact epithelium. The

mechanism of BAK is to change the surface tension in

order to allow riboflavine to penetrate the cornea. The

advantages are: less invasive, fewer complications,

increased patient comfort (6).

Postoperative management:

The therapeutic contact lenses are applied for 4-5

days. The patient will use local antibiotic, steroids and

lubricants for 4-6 weeks. The check up is at 28, 48 hours

and at day 4 or 5 to remove the contact lens. The follow

up is at 6 weeks, 3, 6, 9, 12 months after CXL.

Results of Cross-Linking in Keratoconus

Concerning the topography, the frontal apical

elevation showed a significant reduction starting from the

2nd month after surgery (25). The spherical aberration

and high orders doesn’t show statistically significant

variations. The coma aberration is highly reduced from

the first month after CXL.

Regarding the keratometric values there is a

regression of aprox. 2D in 70% of patients (18,24) after 3-

6 months from CXL. Other authors (21) revealed a mean

K reduction of 2.1D.

About the refractive errors they were reduced

with 1,14D (20). Spoerl and col. (18) showed a reduction

of spherical equivalent of 2,5D.

The pachymetry (ultrasonic pachymetry) showed

a little increase in the first month (because of the

postoperative corneal edema) and after 3 months no

significant changes were observed (23).

The visual acuity with and without correction

improved in 68% (21), with one or two Snellen lines at 3

months, even if the procedure is not a refractive one.

Cross-Linking offers the stability of the cornea.

For visual rehabilitation (after 6 months) we can associate

a therapeutic partial topography-guided PRK on cross-

linked cornea (3) or intracorneal rings. Both this methods

normalizes the corneal surface by reducing irregular

Astigmatism, and potentially the refractive error as well.

Cross-Linking in bullous keratoplasty (BK)

For a normal activity, cornea needs a normal

endothelial pump function. No endothelial pump function

gives swelling of the cornea and fluids accumulates in

extracellular spaces between the collagen fibers and

lamellae (16).

The principle of CXL in BK is the concept of

stromal compaction with enhanced resistance to osmotic

and hydrostatic fluid accumulation (12).

Cross-Linking in corneal ulceration and melting The principle of Cross-Linking in this severe

keratites is to increase resistance to collagénase, pepsin,

trypsin digestion, especially in the anterior half of the

cornea (the biochemical effect of CXL).

Spoerl and col. (19) showed in Cross-Linked

pigs eyes the doubling of the digestion time of enzyme.

Cross-Linking in pathologic Myopia

The principle of CXL in high Myopia is to

change in the biomechanical weakened sclera.

Wollansek (22) and Iseli (10) studied the CXL

made on the sclera in living rabbit eyes. The results

showed an increase in stiffening.

Take home messages

1. The biomechanical strength of the cornea is

abnormally low in keratoconus patients, which may

play a role in the progression of the disease.

2. CXL may hold the progression of keratoconus, by

strengthening individual corneal collagen fibers.

3. CXL ages the cornea 600 years in approximately 600

seconds.

4. Uses of CXL are multiplying: keratoconus, pellucid

marginal degeneration, postlasik ectasia, bullous

keratopathy and pathologic myopia.

5. Modified treatment parameters for CXL may be used

in patients with advanced keratectasia who can still

achieve satisfying visual acuity with contact lenses.

6. Hipoosmolar riboflavin solution can be used to

increase corneal depth in corneas too thin for

standard protocol.


AMT, vol II, nr. 1, 2010, pag. 54

7. The treatment must prevent damage to the corneal

endothelium, iris, lens and retina.

8. Simultaneous surface ablation with CXL produces

topographic improvements and visual reabilitation.

9. ICRS regularize the front surface of the cornea by

building tissue in the mid-periphery.

REFERENCES 1. Albe E. Measuring corneal biomechanical properties

in keratoconic eyes undergoing crosslinking.Cataract

and Refractive Surgery Today Europe 2008;5;33-34

2. Andreasson TT, Simonsen AH, Oxlund

H.Biomechanical properties of keratoconus and

normal cornea.Exp Eye Res 1980; 312:435-444

3. Braun E, Kanellopoulos J, Pe L Jankov

M.Ribovlavin/Ultraviolet-A-induced collagen cross-

linking in the Management of Keratoconus.Invest

Ophthalmol Vis Sci.2005; 46;4964

4. Charters L, Numerous risk factors found for corneal

ectasia after Lasik.Ophthalmology Times .Aug

1,2007

5. Corkin R., CXL Indications and Patient Selection.J

Cataract Refract Surg.2009;04;32-33

6. Elshawaf HI. TCXL Trasepithelial corneal cross-

linking. Paper presented at the IV International

Congres of CXL December 5-6 2008 Dresden

Germany

7. Elsheikh A, Brown M, Alhasso D, Rama P,

Campanelli M, Garway-Heath D.Experimental

assessment of corneal anisotrophy.J Refract

Surg.2008; 24;178-187

8. Hadley JC, Meek KM, Malik NS.The effect of

glycation on charge distribution and swelling

behaviour of corneal and scleral collagen.Invest

Ophthalmol Vis Sci. 1996;37; S1010.

9. Hafezi F, Mrochen M, Iseli Hp, Seiler T, Collagen

Cross Linking with UVA and

hypoosmolarRiboflavin solution in thin corneas.


10. Iseli PH, Spoerl E, Wiedermann P, Krueger RR,

Seiler T. Efficacy and safty of blue light scleral

cross-linking. J Refract Surg 2008;24:752-755

11. Krachmer JH, Feder RS, Berlin MW.Keratoconus

and related noninflammatory corneal thinning

disorders.Surv Ophthalmol1984;28:293-322

12. Krueger RR, Ramos-Esteban JC, How might corneal

elasticity help us understand diabetes and intraocular

pressure?J Refract Surg. 2007; 23;85-88

13. Luce DA.Determining in vivo biomechanical

properties of the cornea with an ocular response

analyser.J Cataract Refract Surg.2005;31;156-162

14. Marshall J, Knox-Cartwright N., Does CXL Promote

Artificial Aging. J. Cataract Refract

Surg.2009;04;22-23

15. Muller L, Pels E, Vrensen G.The specific architecture

of the anterior stroma accounts for maintenance of

corneal curvature.Br J Ophthalmol.2001; 85; 437-443

16. Rao GN, Aquavela JV, Goldberg SH, Berg SL

Pseudofakic bullos kerathopaty. Relation ship to

preoperative corneal endothelial status.

Ophtalmology 1984; 91:1135-1140

17. Seiler T, Huhle S, Spoerl E, Kunath H.Manifest

diabetes and keratoconus: A retrospective case-

control study.Graefes Arch Clin Exp Ophthalmol.

2000; 238:822-825

18. Spoerl E , Huhle M, Seiler T. Induction of crosslinks

in corneal tissue. Exp Eye Res. 1998;66;97-103

19. Spoerl E, Wollensak G, Seiler T.Increased resistance

of crosslinked cornea against enzymatic

digestion.Current Eye Research 2004;24:35-40

20. Spoerl E, Wollensak G, Dittert DD, Seiler

Thermomechanical behaviour of colagen cross-link

porcine cornea. Ophtalmologica 2004; 218:136-140

21. Wollensack G, Spoerl E, Seiler

T.Roboflavin/Ultraviolet A induced collagen cross

linking for treatment of the keratoconus.AM J

Ophthalmol 2003;135;620-627

22. Wollensak G, Iomdina E.Long-term biomechanical

properties of rabbit cornea after photodynamic

collagen cross-linking.Acra Ophthalmol.2009;87;48-

51

23. Wollensak G, Spoerl E, Seiler T. Stress –strain

measurements of human and porcine corneas after

riboflavin –ultraviolet –A-induced cross linking.J


24. Wollensak G, Wilsch M, Spoerl E, Seiler T.Collagen

Fibril diameter in the rabbit cornea after collagen

cross-linkung by riboflavin/UV-A.Cornea 2004;

23;503-507

25. Wollensak G.Crosslinking treatment of progressive

keratoconus;new hope.Curr Opin Ophthalmol

2006;17(4);356-360

26. Zadok D, Goldich Y, Barkana Y, Rasko A and Avni

I. Influence of UV-A-riboflavin corneal collagen

cross-linking on biomechanical properties of

keratoconic eyes.Paper presented at the 2008 ASCRS

annual Meeting ; April 4-9 2008;Chicago


AMT, vol II, nr. 1, 2010, pag. 55

CORRECTION OF PRESBYOPIA WITH CONTACT

LENSES

DANIELA GOICEA

Medicover, Bucharest

Abstract: Population ageing is an issue in all the

developed European countries. Romania encounters a

special situation, due to reaching the presbyopic age of

people born after the Decree 770/1966 banning

abortions, which resulted in doubled natality next years.

On the other hand, about 20 years ago the first contact

lenses started to enter on the Romanian market. Those

who shifted to contact lenses at that moment became or

will soon become presbyops. Therefore, is appropriate to

be prepared to offer a solution to presbyops who do not

want to wear glasses.

Keywords: presbyopia, monovision, multifocal contact

lenses

Rezumat: În toate tarile europene dezvoltate se vorbeşte

despre îmbătrânirea populaţiei. In România exista o

situaţie aparte legata de ajungerea la vârsta prezbiopiei a

celor nascuti in urma decretului de interzicere a avortului

(770/1966), care a avut ca rezultat dublarea natalitatii in

anii următori. Pe de alta parte, in urma cu aproape 20 de

ani pătrundeau pe piaţa romaneasca primele lentile de

contact. Cei care au început atunci sa le poarte au

devenit sau vor deveni curând prezbiopi. De aceea, este

bine sa fim pregătiţi sa oferim o soluţie prezbiopilor care

nu doresc sa poarte ochelari.

Cuvinte cheie: presbiopia, monovision, lentile de contact

multifocale

INTRODUCERE

Contact lenses

Monovision – an acceptable compromise … for some

patients

Monovision is the correction for distance in one

eye (usually the dominant eye), and for near in the other

eye. It is based on the principle that the visual system

selects the clear image at the desired distance, alternating

the central suppression between the 2 eyes when the

viewing is alternating between distance and near targets.

The success of fitting depends on the degree of

suppression, which varies from patient to patient. The rate

of success of monovision is between 67 and 86 %.

Benefits

- Easy to prescribe.

- All kinds of contact lenses (spherical/toric, various

materials) can be used.

- Is not related to pupil size.

- Does not compromise the view in low lighting or

blunt contrast.

- Minimal compromise in near vision performance –

may be recommended to those with strong near

vision demands.

Disadvantages

- Loss of stereo acuity, especially for high additions.

- Loss of contrast and difficulty in suppressing bright

images on dark background.

- Some patients can not adapt due to difficulties in

suppressing one eye.

- Problems can appear in depth perception.

o Drivers have to be warned.

o Can be solved by wearing glasses over CL.

- Compromises the vision at very far and very near

(difficulties for several activities: night driving,

playing golf, reading for long time).

Partial monovision

Is recommended when presbyopia advances, as

the add exceeds +2.00D and the monovision is not

accepted anymore. The addition has to be reduced on the

eye corrected for near and the sub-correction has to be

compensated with supplementary glasses for small print.

In addition, glasses for distance can be supplementary

recommended for driving. Such correction may be

suitable for patients who need especially better

intermediate vision.

Multifocal contact lenses

Bifocal and multifocal contact lenses are based

on two types of design: alternating vision and

simultaneous vision

Alternating vision lenses

Similar to bifocal glasses, the lens has 2 distinct

areas – one superior for distance vision and other inferior

for near vision. For distance vision, the patient looks

straight and is seeing through the superior part of the lens.

In downward gaze for reading, the lens is pushed upward

by the inferior lid and the patient looks through the

inferior part of the lens, which contains the addition for

near. The stability of the lenses is obtained through

bottom thickness (prism ballast), truncating or both.

Simultaneous vision lenses

The zones for distance, intermediate and near

vision are disposed concentric in front of the pupil, the

image of any object being formed throughout all optical


AMT, vol II, nr. 1, 2010, pag. 56

zones. When a distance object is fixed, the optical zone

for distance produces a focused image, while a blurred

image is produced on the retina through the near zone.

The visual system is able to select the clearer desired

image and to ignore the others.

The performance of the lens depends on the

pupil size and on the lens centration.

There are three types of design for simultaneous

vision: multi-zone concentric, diffractive and aspheric.

Multi-zone concentric design

There are several alternative concentric zones for

distance and near vision. The quality of vision at any

distance depends on the quantity of light entering the eye

through the distance or near zones. The quantity of light is

regulated by pupil dimension. It favors distance vision in

extremely bright or in very reduced light. In ambient

illumination a more equal light distribution through

distance and near zones is provided.

Aspheric design

Addition powers are concentric and gradually

change from geometric center through the edge of optical

zone. There are 2 types of aspheric design – centre-near

and centre-distance. There is an issue related to the

centre-distance lenses due to the fact that at near vision

the pupil is constricting, blocking thus the vision through

the periphery, which is actually meant for near vision.

Such problem is solved by the centre-near design. The

two multifocal Silicon hydrogel lenses available on

Romanian market have centre-near design.

Prescription of multifocal lenses

A. Refraction

1. Determining the distance power

The distance power is determined through an as

careful as possible refraction and choosing the least minus

or most plus. +/-0.25Dsph may affect patient vision and

satisfaction. We have to take into account that at this age

the hyperopia is slightly increasing. Over-correction of

myopia or sub-correction of hyperopia may lead to a

higher-than-necessary add power.

The distance power of multifocal lens is

determined applying the correction for vertex distance of

the spherical equivalent. An astigmatism higher than

1. Dcyl. should not be ignored because it adds to high

aberrations.

2. Determining the addition

3. Determining the dominant eye (for example through

+2,00Dsph test)

B. Trial with multifocal contact lens

- Allow the lenses to settle about 10 minutes.

- Evaluate the fitting with the slit-lamp (centration,

movement).

- Check binocularly the distance and near vision, under

normal room illumination.

- Over-refract with hand-held trial lenses. The

phoropter should be avoided as it affects the near

accommodative response and pupil size.

Improving distance vision

• Increase the minus in distance lens power

– By -0.25Dsph in dominant eye or both eyes

– Check subjective and objective improvement to

distance vision

– Check that near vision remain unchanged or

acceptable

– Continue to add minus power if further distance

vision improvement is confirmed, while near

vision does not alter

• Reduce add power – in one or both eyes

• “Modified monovision“

• “Enhanced monovision”

Improving near vision

• Increase the plus in distance lens power

– By +0.25Dsph in non-dominant eye or both eyes

– Check subjective and objective improvement to

near vision

– Check that distance vision remain unchanged or

acceptable

– Adding plus power only to non-dominant eye may

reduce the risk to alter the distance vision,

meanwhile improving near vision

• Increase add power

• “Modified monovision“

• “Enhanced monovision”

Modified monovision

It consists in fitting multifocal lenses in both

eyes, but with the aim to improve distance vision in one

eye (at the expense of near performance) and near vision

in the other. Improving distance vision on the dominant

eye is achieved by increasing the minus / decreasing the

plus for distance power, decreasing the addition or

choosing the centre-distance design. Improving near

vision on the non-dominant eye is achieved by increasing

the plus / decreasing the minus for distance power,

increasing the addition or choosing the centre-near design.


AMT, vol II, nr. 1, 2010, pag. 57

Enhanced monovision

It consists in fitting one eye with a single-vision

distance lens (usually in the dominant eye), and the other

with a bifocal or multifocal lens. Such correction is useful

for patients fitted with multifocal lenses, which are not

satisfied by the distance vision, as well as for monovision

wearers who need high additions, with the aim to improve

stereoacuity. Seldom, may be recommended a single-

vision near lens on the dominant eye and a bifocal or

multifocal lens on the other eye for patients interested

especially in the near view.

Patient approach

An interesting idea is to approach the patient

before presbyopia appears, according to Sarah Morgan:

“It’s not what we tell our presbyopic patients, it’s what

we tell our PRE-presbyopic patients that counts.

Forecasting their vision future promotes confidence and

places the eye care professional as a visionary – and an

authority on vision. Explaining presbyopia to patients is

the first step and discussing it, before prespyopia strikes,

is prudent.”

After presbyopia appears, we should present to

the patients all correction modalities, enhancing their

benefits and limits, and recommend the appropriate option

for each one. Presenting all the options, they can not say

“nobody told me this”.

Practitioners who are successful in fitting

multifocals state that the communication is essential. Here

are some advices:

• Be enthusiastic!

Mention multifocal lenses to every possible

candidate! You may say: ”Did you know that there are

contact lenses which allows you to see at near without

glasses?”

• Be optimistic!

“Wearing contact lenses is the “secret” way to

see at all distances, while looking all around.”

• Establish realistic expectations!

“Multifocals improve the vision and reduce the

need for glasses.” The patient should know that contact

lenses will help in usual activities – viewing a cell-phone,

working on computer, reading newspapers – but might be

situations in which glasses will be of help.

• Offer a “test drive”

Encourage the patient to test the vision with

multifocals in day-by day life. The patient should wear

the lenses about one week, after which they should come

back for adjustments. State that afterwards you can

improve the initial prescription, which was only a starting

point. Insist that they should wear the lenses during trial

period, scoring the quality of near and distance vision.

CONCLUSION

There are now various options to correct

prebyopia with contact lenses. The new simultaneous

vision lenses, comfortable and with increased optical

performance are easy to fit, and the availability of single-

use diagnostic trial lens allows the patients to experiment

and to enjoy their advantages.

BIBLIOGRAPHY 1. Nathan Efron, Contact lens practice, Reed

Educational and Professional Publishing Ltd 2002

2. Mile Brujic, Tips from the Trenches, Review of

Cornea and Contact Lens, 2009

3. Sarah Morgan, Presbyopia happens, CIBA VISION,

2009

4. Kathryn Richdale, Ocular and Refractive

Considerations for the Ageing Aye, CLSpectrum,

2009

5. Jane Schofield, Multifocal contact lenses – from

opportunity to success, Dispensing Optics, 2009

6. Dimple Shah, Life Begins at Presbyopia, Academy

for Eyecare Excellence, 2009


AMT, vol II, nr. 1, 2010, pag. 58

THERAPEUTIC CONTACT LENS IN THE ANTERIOR

POLE SURGERY COMPLICATIONS

ADRIANA STĂNILĂ, A. TEODORU, ELENA MIHAI, MIHAELA FLORESCU,

V. RUSU, I. COSTACHE

Ocular Surface Research Center Sibiu, Emergency Hospital Sibiu, “Lucian Blaga” University Sibiu

Abstract: Aim Of Study: this study reveals some

complications of the anterior pole surgery where the use

of therapeutic contact lenses (TCL) proved to be of great

benefit. Matherial, Method: We used TCL for the

management of wound dehiscence (after cataract surgery)

and excessive filtration (after glaucoma surgery). Results,

discussions: The small wound dehiscences after cataract

surgery (through small incisions for phacoemulsification)

were solved within a few days using only a TCL, without

re-suturing the wound. The excessive filtration after

glaucoma surgery turned to normal using TCL. The

applying of LCT in bullous keratopaty reduced

significantly the symptoms in all cases.Conclusions: The

using of TCL in these cases offer new and simple

solutions for the management of nearly common

complication encountered after anterior pole surgery.

Keywords: therapeutic contact lens, anterior pole surgery

Rezumat: Scopul lucrării: studiul evidenţiaza unele

complicaţii ale chirurgiei polului anterior in care lentila

de contact terapeutică s-a dovedit eficientă. Material,

metodă: am utilizat LCT în dehiscenţe de plagă după

operaţia de cataractă, în situaţiile cu exces de filtrare

după chirurgia glaucomului şi în keratopatia edemato

buloasă. Rezultate, discuţii: dehiscenţele mici după

chirurgia cataractei (facoemulsificare) s-au rezolvat

pozitiv în câteva zile după aplicarea lentilei. Excesul de

filtrare după operaţia de glaucom s-a normalizat folosind

LCT. Simptomatologia s-a ameliorat în keratopatia

edemato-buloasă prin aplicarea de LCT. Concluzii:

folosirea LCT oferă o soluţie nouă şi simplă la unele

complicaţii aparute în urma chirurgiei de pol anterior.

Cuvinte cheie: lentila de contact terapeutică, chirurgia

polului anterior

AIM OF STUDY

This study reveals some complications of the

anterior pole surgery where the use of therapeutic contact

lenses (TCL) proved to be of great benefit.

MATHERIAL AND METHOD

We used TCL for the management of wound

dehiscence (after cataract surgery), excessive filtration

(after glaucoma surgery), edemato-bullous keratopathy.

RESULTS AND DISCUSSIONS

The small wound dehiscences after cataract

surgery (through small incisions for phacoemulsification)

were solved within a few days using only a TCL, without

re-suturing the wound.

We studied a group of 570 patients hospitalized

in the Department of Ophthalmology Clinic of the

Emergency Hospital Sibiu during 2007 - 2008, with the

diagnosis of cataract.

All cases were operated using the extracapsulare

extraction of the cataract by phacoemulsification.

4 cases (0,70%) presented wound dehiscence in

the first postoperative day (small anterior chamber,

without iris inclavation).

2 cases were related with thermal injury of the

main incision, the correlation being statistic significant

(p<0,05).

In all cases we applied a therapeutic contact lens

(fig. 1). No surgical intervention was required.

Figure no. 1. TCL in wound dehiscence

In 3 cases with excessive filtration after

glaucoma surgery we applied TCL (2007-2009). The

filtration turned to normal using TCL in few days and the

anterior chamber became normal (fig.2)

Pain and foreign body sensation in bullous

keratopathy are due to the rupture of the vesicles formed

in the cornea because of the endothelial dysfunction.

Aplying of LCT in the cases with bullous

keratopathy reduced significantly the symptoms (fig.3).


AMT, vol II, nr. 1, 2010, pag. 59

Figure no. 2. TCL in excessive filtration after

glaucoma surgery

Figure no. 3. LCT in bullous keratopathy

CONCLUSIONS

The using of TCL in these cases offer new and

simple solutions for the management of nearly

common complication encountered after anterior pole

surgery.

The thermic injury of the wound was statistic

corelated (p<0,01) with postoperatory wound

dehiscence. We demonstrated that small dehiscences

can be successfully solved by applying a TCL

without suture.

Excesive filtration after glaucoma surgery can be

managed with TCL.

The symptomatology of EBK regresses under the

protection of the lens.

BIBLIOGRAPHY 1. Ryan R.A. Rochester O.D. -23rd Annual Contact

Lens Report, 2000;

2. Stanila A. - Oftalmologie ,Ghid practic, Ed Imago

Sibiu, 2000, pg 72-74, 115

3. Kanski J.J. – Clinical Ophthalmology, 5-th Edition,

2003, 405;

4. Douglas J. Rhee, Marc F. Pyfer- The Wills Eye

Manual: Office and Emergency Room Diagnosis and

Treatment of eye Disease, 3rd edition, Lippincot,

Williams& Wilkins, 1999, pg 61-63,67,112


AMT, vol II, nr. 1, 2010, pag. 60

APLICAŢII ALE LENTILELOR DE CONTACT

TERAPEUTICE

SIMONA RADU

SC Euro-Optics SRL, Bucureşti

Abstract: Therapeutic contact lenses are special contact

lenses worn for the treatment of corneal or anterior eye

diseases and injuries. They are primarily used for pain

relief and increase of comfort, assistance of wound

healing, mechanical protection, maintenance of ocular

surface hydration and as a vehicle for drug delivery. The

use of plano or powered contact lenses may also preserve

or enhance vision in injured eyes. Therapeutic lenses are

particularly useful for post surgical management of the

patients (pterygium, cataract and glaucoma surgery;

keratoplasty; refractive surgery; collagen cross linking;

amniotic membrane) as they allow the cell growth and

adhesion to take place without interference from the

blinking eyelids and also protect the eyelids from

irritations caused by sutures. The materials used for

therapeutic contact lenses are hydrogels, silicone

elastomers, collagen, and gas permeable polymers in the

form of scleral lenses. Soft lenses are preferred because

of the large diameter, supple nature, low movement

amplitude and enhanced comfort. Hydrogel lenses,

however, dehydrate on the eye and the relatively low Dk

may induce hypoxia, as therapeutic contact lenses are

used in the continuous mode. Silicone hydrogel lenses,

available since 1999 and approved for therapeutic use,

became the first choice because of very high oxygen

transmissibility, lower on-eye dehydration and good

comfort and coverage of the eye surface.

Keywords: therapeutic contact lenses, silicon-hidrogel

materials

Rezumat: Lentilele de contact terapeutice sunt definite ca

lentile de contact folosite în tratamentul unor afecţiuni şi

traumatisme oculare. Ele au ca efecte principale:

reducerea durerii şi creşterea confortului, asistarea

reparării tisulare, protecţie mecanică, menţinerea

hidratării suprafeţei oculare şi rezervor de substanţe

medicamentoase. Pot avea şi rolul de a menţine sau

îmbunătăţi vederea. Lentilele terapeutice sunt incluse şi

în cadrul protocolului postoperator în cazul anumitor

afecţiuni şi complicaţii chirurgicale (pterigion, chirurgia

cataractei şi a glaucomului, keratoplastii, chirurgie

refractivă, collagen crosslinking, transplant de membrană

amniotică) deoarece permit creşterea şi adeziunea

celulelor corneene fără interferenţa clipitului şi

protejează pleoapele de iritaţiile cauzate de firele de

sutură. Materialele folosite sunt diverse: hidrogel,

elastomeri siliconici, collagen, polimeri gaz permeabili în

forma de lentile sclerale. Lentilele moi sunt în general

preferate datorită diametrului mare, supleţii, mobilităţii

reduse şi a confortului superior. Lentilele din hidrogel

însă se deshidratează în timpul purtării, iar

transmisibilitatea la oxigen este relativ scăzută şi pot

induce hipoxie, mai ales că sunt folosite în regim

continuu. Lentilele din silicon hidrogel, disponibile din

1999, au devenit prima opţiune datorită înaltei

transmisibilităţi la oxigen, rezistenţei la deshidratare şi

bunei acoperiri a suprafeţei oculare, în conditii de

confort.

Cuvinte cheie: lentile de contact terapeutice, materiale

silicon-hidrogel

INTRODUCTION

Therapeutic contact lenses are special contact

lenses worn for the treatment of corneal or anterior eye

diseases and injuries. The lenses are used in continuous

wear modality, variable periods of time between days and

months, years maybe, handling being performed by

specialist only and are generally associated with topical

medication.

Today practitioners may choose between more

sophisticated materials (1)(with higher oxygen

transmissibility –RGPs and silicon-hydrogels), improved

lens designs and lens care and replacement options (2),

things that lead to a greater success with therapeutic

lenses in a wide range of anterior segment pathologies.

Also there are new refractive surgery techniques

that include therapeutic contact lenses in their protocol. .

Functions of the TCL

We are fitting the therapeutic lens to serve one

main purpose, but the functions are generally associated.

Pain relief

Epithelial lesions are very painful and induce

lacrimation, photofobia, blepharospasm and severe cases

present even anterior inflammation, causing chemosis and

limbal redness. During blinking, the superior eyelid

movement enhances the discomfort. The lens alleviates

pain better than patch.

Mechanical protection

The lens protects the sensitive corneal surface

during blinking, especially in tear film deficiencies (high

friction, lid wiper epitheliopathy) or in cases of post


AMT, vol II, nr. 1, 2010, pag. 61

traumatic or recurrent corneal erosions.

Lenses can be used in lid deformities or scars

that affect their shape or movement with/without

exposure kerathopathy, in trichiazis or cranial nerves

palsies, till surgical treatment.

We can also use therapeutic soft lens in the

piggy-back system in advanced cases of keratoconus, to

protect the tip of the cone from the friction induced by

RGP lens.

After certain surgical procedures (eg.

Keratoplasty), the contact lens can be used to diminish the

irritation of the upper lid because of the sutures or the

uneven host-graft junction.

Promotion of the wound healing

The contact lens protects the wound area from

the interference of the lid during blinking and allows

rapid coverage of the defect and strong adhesions between

cells and to the bazal membrane.

High oxygen transmissibility and low on-eye

dehydration maintains the normal phisiology of the

corneal tissue

Maintenance of corneal epithelial hydration

Severe dry eye is a common contraindication for

contact lens wear, because of intense on-eye dehydration,

mostly in soft hydrogel contact lenses.

However, in certain situations, like Filamentary

Keratitis in Sicca Syndrome, contact lenses can be used to

maintain corneal hidration. Best performance can be

obtained with low water content silicone-hydrogel lenses

or scleral RGPs with high oxygen transmissibility, used

together with lubricant drops.

Structural support

In cases of acute thinning of the cornea, like

Descemetocel, contact lenses can be used as an alternative

to the suture of the eyelids.

Sealing of corneal perforations

The use of TCL in perforating ijuries of the

cornea can eliminate or lower the number the sutures and

reduce the suture-induced astigmatism. Best results in

very small punctures or flaps.(3)

Drug delivery ( collagen shields, soft lenses)

The contact lens can maintain the drugs on the

corneal surface and reduce the number of applications of

medication. Frequent replacement and use of

preservative-free drops is adviceable.

Improving visual acuity

Ussualy therapeutic lenses are produces as

„plano”, but they can improve visual acuity in distorted

corneas, (RGP, silicon-hydrogel special designs) or in

those cases where spectacles are not allowed because of

facial injuries.

Restoring the binocular vision

In small injuries, the use of contact lenses instead

of a patch, preserve vision in monoftalm patients and

restores binocular vision for the others.

Ocular diseases where we can use TCLs for pain relief

Bulous Keratopathy

Decompensation of the corneal endothelium in

posterior corneal distrophies or after surgery causes

corneal oedema and epithelial bulae and painful erosions.

Pain I will be reduced by a steep fit of the therapeutic lens

(4) The TCL wear may be continued indefinitely or just

till penetrating keratoplasty, so the selected TCL should

have a high oxygen transmissibility to reduce the risk of

vascularisation.(5)

Thygeson superficial punctate keratitis

In severe cases, the TCL is used as a pressure

patch, for relieving pain and foreign body sensation.

Filamentary keratitis

Filaments are common in severe dry eye cases

but also after keratoplasty or vitectomy in diabetics. For

persistent cases,TCLs can be used, filaments are showing

resolution in 4 days and dissappearance in 2 weeks, but

they can recur. Patients should receive additional intense

lubrication and be closely observed because of the higher

risk of infection of this cases.

Ocular diseases where we can use TCLs for promoting

wound healing

Recurrent corneal erosions

This painful episodes of epithelial erosions occur

most often after trauma (linear cuts, foreign bodies), in

anterior membrane distrophies (10 %) or even

spontaneously in cases with favorables factors like dry

eye or diabetes. Disposable, steep and thick TCLs used

for 2-6 month may help to formation of healthy strong

adhesion between cells and epithelial basement

membrane.

Persistent corneal epithelial defects after burns or

neurotrophic keratopathies (viral infections in late stages,

tumors, radiotherapy, vascular disesses in trigeminal area)

can be managed by TCLs or collagen shields until new

epithelium reattaches to the newly secreted basement

membrane.

Herpex simplex is a contraindication for TCL

use in acute stages but it can be fitted weeks later for

persistent epithelial defects caused by toxicity of antiviral

medication or neurotrophic keratitis (6)

Exposure keratopathy as a cause of facial palsies

or lid defects may benefit by temporary TCL with intense

lubrication

Descemetocel may lead to perforation and TCl

may be used as an alternative to the suture of the lids,

with topical medication (7)

Ocular diseases where we can use TCLs for

protection

Steven-Johnson syndrome may benefit from

TCL use in late stages for preventing symblefaron

formation and corneal protection. Sleral lenses, large (15-

20mm) thick soft lenses or silicone materials are of

choice.

Severe dry eye

On short term, silicon ruber lenses and scleral

RGPs mai be used for filamentary keratitis

Lid deformities with exposure keratitis,

entropion, trichiazis may be managed by a TCL till

surgical treatment is performed

In advanced cases of keratoconus, piggy-back

system is an option because it helps to protect the


AMT, vol II, nr. 1, 2010, pag. 62

sensitive apex of the cornea and to stabilise the RGP for a

better vision.

Surgical conditions that may appear in cases of ocular

trauma or surgical procedures

Trauma

In corneal abrasions TCLs may be user, instead

of patch,for injuries over 4 mm in size

Corneal lacerations, especially non-infected, limbal

wounds have better recovery and less vascularisation

when a steeper,big diameter and with highy oxygen

transmissibility contact lens is used (8)

Corneal perforations may be easily sealed by

using a TCL with or without cyano-acrylate glue, before

or instead of sutures. In central injuries less astigmatism

is induced.

Chemical burns

TCL may inhibit the passage of certain proteolytic

enzymes present in the tear film to the stroma, thus

preventing the progressive ulcerative process

For peripheral defect low water content soft

lenses may stimulate vascular ingrowth and arrest the

ulcerative process.(9) When the lids are also involved, a

scleral lens is of choice .

In alkali burns - scleral lenses and very large

soft lenses help prevent simblefaron in later stages . (10)

Pterygium

After surgical removal of pterygium, TCL

reduces pain, promotes corneal epithelisation and on long

term may reduce the number and severity of recurrences

by controlling the conjunctival progression towards

cornea during healing.

Cataract

First day postsurgery some unsutured small incisions may

show positive Seidel. TCL mai be used for few days to

stop the leak ans seal the wound.

Glaucoma

Excessive postoperatory drainage of the bleb may benefit

of large TCL (TD 16-20 mm) until the anterior chamber is

completely restored.

Keratoplasty

Surgeons are using TCLs after perforating or

lamellar keratoplasty for improving the confort of the

patient and protect the palpebral conjunctiva from

abrasion caused by the sutures but also in cases that

present delayed epithelial healing, epithelial filament

formation, steps in host – graft jonction, loose sutures. In

this cases lenses are used for pain, protection, healing and

hidration.

After vitrectomy

Diabetics develop epithelial defects after

vitrectomy in about 25% of the cases, so a TCL may

promote healing. TCLs should have high oxigen

transmissibility, used in association with topical

antibiotics and be followed closely because of the higher

risc of infection in this patients,

Refractive surgery

PRK and LASEK include TCLs in their routine,

as they promote healthy wound-healing by preventing

corneal dessication, particularly when surface ablation

leaves the stroma bare – within 4 days.

LASIK procedure may be followed by TCL fit in case of

complications like: thin flaps, free flap, button-hole,

lacerations.(11)

Collagen cross linking with UVA and

Riboflavin A as a treatment for keratoconus progression

and postsurgery ectazia is also using TCls for pain control

and promotion of healing.

Ocular surface reconstruction with amniotic

membrane

Amniotic membrane is a tissue used for

reconstruction of the ocular surface. TCL mai be used to

cover the membrane and to allow the cell growth and

adhesion to take place without interference from the

blinking eyelids and protect the palpebral conjunctiva.

The membrane may be held in place by a smaller numer

of sutures and has a longer therapeutic action.

Contact lens materials

Hydrogel lenses

Soft contact lenses have been preferred for

therapeutic use because their soft and flexile nature and

large variety of parameters that allow an simple and

comfortable fit to any distorted ocular surface. As they

have a permeable structure they maintain the

concentration of topical associated drugs for longer

periods of time with a less frequent instillation

regime.(12)

There are a big number of hydrogels available,

starting from the original Otto Wichterle’s formula -

Polyhydroxyethylmethacrylat (p-HEMA) 38% water

content- by adding different monomers: acid methacrylic

(AM), N-vinyl pyrollidone (NVP), poly vinyl pyrollidone

(PVP), poly vinyl alcohol (PVA) to improve oxygen

permeability and biocompatibility.

According to the water content we have 3 groups in the

European classification :Low water content 38-45% ,Mid-

water content 45-55% and High water content 67-80%

and

In US there are four groups, as they take into

consideration the water content and ionic charge: Group I:

Non - ionic, LWC; Group II: Non - ionic, HWC; Group

III: Ionic, LWC; Grup IV: Ionic, (HWC: > 50 % water,

Ionic : > 0.5 % Methacrilic Acid)

Oxigen permeability is linked to the water

content and to the thickness so the best oxygen

transmissibility is delivered by the thin medium water

content lenses, but it does not exceeds the values needed

for safety values even for daily wear f (Dk/t = 24 for no

corneal edema -Holden & Mert, and Dk/t =35 for absence

of corneal anoxia -Harvitt &Bonnano). When the eye is

closed this values are much bigger (Dk/t = 87,

respectively Dk/t =125.)

(The labeled value of Dk/t is for the central area

-3,00D lens, at 35 °C) (13)

As therapeutic lenses are used in extended wear

modality, hydrogels may induce corneal hypoxia and

neovascularisation and affects corneal phisiology.

During wear, hydrogel lenses dehydrate up to 6%

of their water content that induces a steeper fit in time and


AMT, vol II, nr. 1, 2010, pag. 63

an osmotic stress to the ocular surface. Therefore the lens

should be evaluated again in 20 minutes after insertion.

Ionic materials attract more proteins on their

surface and non-ionic materials are showing more lipid

deposition.(14)

Extra thin glyceryl methacrylate lenses (Crofilcon) are known to have a smaller rate of giant

papillary conjunctivitis.(9)

Silicone elastomer lenses were used for their

extremely high oxygen transmissibility and much less

vascularisation, mostly in children afakia. The

hydrophobic nature of the material induces heavy lipid

deposits and they tend to stick to the ocular surface.

Silicone- Hydrogel materials

First models have been introduced in 1999

(Lotrafilcon A and Balafilcon A ) and very soon they

received FDA approval for therapeutic use for maximum

30 days of continuous wear.

Advantages of this combination are: high

permeability to oxygen , water and sodium, therefore a

high oxygen supply to the cornea, as a result the hypoxic

stress in overnight wear is dramatically reduced;

flexibility; lower water content with a low dehydration

during wear and a stable post lens tear film; good surface

wettability achieved by surface treatment (by plasma

coating or oxidation) and less deposits ( some lipid, non-

alergenic depositions).

There are still some disadvantages: limited

parameters (relatively small diameter), concurrent

medication should be non-preserved, and risk of

complications associated with extended wear (microbial

keratitis, infiltrates). Modulus has also relative high

values so the incidence of inflammatory reactions is

relatively high (infiltrates, papillary conjunctivitis,

superior epithelial arcuate lessions) despite availability of

different base curves for better fit. (15) Surface treatment

is also expensive.

Since 2004 other products have been released on

the market, some with internal wetting agents (eg.

Galyfilcon A, Senofilcon A) (16) or with natural wetting

macromer combination (Comfilcon A, Enfilcon A) that

eliminate the need for surface treatment and one with the

same coating but lower modulus (Lotrafilcon B)

Some of this products ghave received approval

for extended wear up to 7 days and 6 nights (lotrafilcon B,

senofilcon A) or continuous wear for 30 days and nights

(Comfilcon A).

The advantages of the new generations are

improved flexibility and wetability without surface

treatment so the production ad replacement costs

diminished.

Rigid gas permeable lenses and scleral lenses and

rings, with high oxigen transmissibility, may be used for

therapeutic purpose, in specific cases where we need

prevention of simblepharon formation, maintainance of

corneal hidration and on distorted corneas. The

disadvantages are the initial discomfort and longer time

for fitting.

Collagen shields may be also used as corneal

bandage. They are made of bovine or porcine collagen,

have a Dk/t equivalent of a 63% water soft lens, mai be

soaked in antibiotics, and they last for 12,24 or 72 hours,

as they biodegrade on eye.

Instrumentation For therapeutical contact lens fit instrumentation

is simple: slit-lamp (examination should be performed in

difuse or lower light intensity because of photophobia),

dyes (Fluoresceine, rose bengal, lissamine green),

Schirmer test, keratometer (measuremet of the fellow

eye), topography (for RGPs). Anesthetics should be used

only in small amounts.

Selection of therapeutic contact lens should be

made according to the specific disorder, oxygen

transmissibility, parameter range, parameter stability,

wettability of surface, lubricity, deposits (non –ionic

hidrogel and silicone hydrogel attract more lipids, build-

up is liniar in timp but do not induce allergies)(14),

modulus, costs.

Fitting of the lens

The lenses should be fitted with great care fore

good corneal coverage and mobility.

With intact epithelium or corneal oedema fit should be

normal to loose, for good tear exchange

For pain relief or in cases where epithelium is

not intact or topography is irregular, steep fit is better,

achieved by increasing lens diameter or reducing the base

curve of the lens. Edge design of soft lens has a major

impact on mobility.

Fit should be assessed in 20 min and again in 60

min to unmask the dehydration effects.

Aftercare is minimum, patient should be

compliant and follow doctors recomandations regarding

hygene, local treatment and check-up schedule. Follow-up

will be performed at 24h, 72h, 1 week, 2weeks, and

monthly, according to the case. Lenses should be replaced

at 1 week or 1 month.

Complications of therapeutic contact lenses are

the same as for all contact lenses: corneal edema, corneal

vascularisation, corneal infiltrates, staining, deposits,

giant papilary conjunctivitis, hypopyon, infection. Risk is

even higher as lenses are used in extended wear

modalities, topical steroids may be associated and

immune system or the patients may be compromised

(diabetes). Associated topical drugs should be

preservative free or the lens should be discarded weekly,

to avoid toxicity.

There are patient-related risks: severity of

disease, dry eye, topical steroids, compliance, hygiene,

general health, motivation and lens-related risks: hypoxia,

deposition, mechanical insult, poor fit, extended wear

that have to be taken into consideration when fitting and

monitoring a TCL.(17)

CONCLUSIONS TCLs are offering great benefits in the treatment

of ocular surface pathology.

Soft lenses are preferred because of the large

diameter, supple nature, low movement amplitude and


AMT, vol II, nr. 1, 2010, pag. 64

enhanced comfort. Hydrogel lenses, however, dehydrate

on the eye and the relatively low Dk may induce hypoxia,

as therapeutic contact lenses are used in the continuous

mode.

Silicone hydrogel lenses, available since 1999

and approved for therapeutic use, became the first choice

because of very high oxygen transmissibility, lower on-

eye dehydration and good comfort and coverage of the

eye surface.

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AMT, vol II, nr. 1, 2010, pag. 65

BANDAGE CONTACT LENSES FOR RECURRENT

CORNEAL EROSIONS

SIMONA RADU

FIACLE, SC Euro-Optics SRL, Bucharest

Abstract: Recurrent Corneal Erosions (RCE) syndrome is

a condition that is characterized by a disturbance at the

level of the corneal epithelial basement membrane,

resulting in defective adhesions and recurrent

breakdowns of the epithelium. It may appear secondary to

corneal injury (after trauma or surgery) or

spontaneously, in cases with predisposing factors, such as

corneal dystrophies ,diabetes, dry eye. Management of

RCE may be medical treatment (lubricants, ointments,

patch, bandage contact lenses etc) but also a variety of

surgical procedures are recommended. Aim of the paper:

to evaluate the success of therapeutic contact lenses in the

management of recurrent corneal erosions. Matherial and

Method: 27 cases of recurrent corneal erosions (2006-

2009). 20 of them (macroform cases) were fitted with

silicone-hydrogel TCL (moderate steep fit) used for 1-3

months, associated with preservative free lubricants..

Discussions and results: Recurrent erosions were

posttraumatic (16), anterior basement membrane

dystrophies (3), dry eye (6), secondary to microbial

corneal ulcer (1) and kerato-conjunctivitis (1). There

were no complications (no infection, no infiltrates, no

neovascularisation). Conclusions: The success of this

simple procedure depends on cause of the recurrent

erosions, associated factors , type and fit of TCL, long-

term use, proper patient education .The use of the

therapeutic bandage lenses is a useful and simple way to

treat recurrent corneal erosions in any non-surgical

ophthalmological unit.

Keywords: Recurrent corneal erosions, therapeutic

contact lenses

Rezumat: Sindromul de eroziuni corneene recidivante

(ECR) este o afecţiune caracterizată printr-o deficienţă a

membranei bazale a epiteliului cornean ce are ca rezultat

o aderenţă scăzută şi soluţii de continuitate recurente ale

epiteliului. Apare cel mai frecvent dupa un traumatism

cornean (accidental sau chirurgical) sau spontan dacă

există factori predispozanţi cum ar fi distrofiile corneene,

diabetul, ochiul uscat. Tratamentul eroziunilor corneene

recidivante poate fi medical (lubrefianţi, unguente,

pansament compresiv, lentile de contact terapeutice sau

chirurgical. Scopul lucrării: De a evalua succesul

utilizării lentilelor de contact terapeutice în tratamentul

eroziunilor corneene recidivante. Material şi metodă:

Analiza retrospectivă a 27 de cazuri de eroziuni corneene

recidivante, în perioada 2006-2009. In cazurile cu

alterări epiteliale vizibile (20), s-a utilizat timp de 1-3

luni o lentilă de contact din silicon-hidrogel, adaptată

strâns, asociată cu lacrimi artificiale fără conservanţi.

Rezultate şi discuţii: 16 dintre eroziunile recidivante au

apărut posttraumatic, 3 cazuri prezentau distrofii de

membrană anterioară, 6 cazuri ochi uscat moderat sau

sever, un caz a fost secundar unui ulcer cornean şi altul

unei kerato-conjunctivite. Nu au existat complicaţii

(infecţii, infiltrate sau vase de neoformaţie).Concluzii:

Succesul acestei proceduri simple depinde de cauza

eroziunilor recurente, factorii asociaţi, tipul lentilei de

contact terapeutice şi modul de adaptare, utilizarea ei pe

o perioadă mai lungă de timp, educarea pacientului.

Lentilele de contact terapeutice se dovedesc eficiente în

tratamentul eroziunilor corneene recidivante şi sunt uşor

de folosit în orice unitate oftalmologică non-chirurgicală.

Cuvinte cheie: Eroziuni corneene recidivante, lentilă de

contact terapeutică

INTRODUCTION

Recurrent Corneal Erosions (RCE) syndrome

is a condition that is characterized by a disturbance at the

level of the corneal epithelial basement membrane,

resulting in defective adhesions and recurrent breakdowns

of the epithelium.(1)

Improper healing of epithelial basement

membrane or inadequate hemidesmosomes formation and

adhesion to the stroma results in epithelial loss,

microcysts, and bullae.

Multiple recurrences are common because the

basal epithelial cells require at least 8-12 weeks for

regenerating or repairing the epithelial basement

membrane and pain is the most disturbing symptom.

Causes

1. Secondary to corneal injury. Most cases occur after

accidental trauma (especially wounds with sharp

edges or with foreign bodies), burns or corneal

ulcers.(2) Surgical procedures like refractive surgery,

vitrectomy may be followed by improper healing of

the bazal membrane of the epithelium. Long term use

of topical medication like antibiotics, anesthetics, by

their own toxicity or by preservatives may

deteriorate the ocular surface balance

2. Spontaneously. Recurrent corneal erosions may occur

spontaneously in cases with predisposing factors,

such as: corneal dystrophies, diabetes, dry eye. 2% of

the population develop anterior membrane

dystrophies out of witch 10% experience repeated


AMT, vol II, nr. 1, 2010, pag. 66

episodes of corneal erosions.(3)

Management of RCE

Medical treatment. Generally we treat corneal

erosions by lubricants, ointments, sodium chloride

5%,pressure patch, bandage contact lenses sometimes

with punctal closure.(4,5,6)

Surgical treatment. There are many surgical

options(7) in the treatment of recurrent corneal

erosions, more or less invasive some of them using

sophisticated tools:

- Epithelial debridement (mechanical/alcohol)

- Diamont burr polishing of the Bowman layer

- Anterior stromal puncture

- Nd:YAG laser treatment for Bowman layer

- Excimer laser phototherapeutic keratectomy

AIM OF STUDY

To evaluate the need and the success of

therapeutic contact lenses in the management of recurrent

corneal erosions


Retrospective analisys of 27 cases of recurrent

corneal erosions, between 2006-2009.

In all cases patients were evaluated by careful

anamnesis, refractometry, VA, biomicroscopy with

fluoresceine in all cases and rose bengal in one case, BUT

and Schirmer test.

Treatment In cases without visible epithelial defect , were

recommended lubricants, ointments at bed-time and

dietary suplements ( omega 3 fatt acids, vitamine A)

Where epithelial defect was present the patient

was fitted with disposable bandage contact lenses, silicon-

hidrogel material, continuous wear: Lotrafilcon A,

available in 2 base curves ( 8,4 and 8,6) and Balafilcon A

(8,6), with no anesthetic drops. Topical treatment used -

artificial tears preservative free. In cases where epithelium

was loose it was removed by debridement with a sterile

cotton-tip stick prior to contact lens insertion.

Check-up was done next day, in one week and

monthly.

DISCUSSIONS AND RESULTS

Age of the patients was between 9 and 76 years

old with an average of 42. were females and only 3 men.

In 3 cases there were bilateral, alternative episodes. 16 of

the cases had a history of trauma (paper-cut, fingernails,

foreign bodies, burns), one of which showed later signs of

finger-dot dystrophy, 3 anterior basement membrane

distrophyes, 6 cases had moderate and severe dry eye, (2

cases had tyroid disease with substitution medication),

one was secondary to a microbial corneal ulcer and one

had a history of 6 month of medication after microbial

conjunctivitis.

7 cases (from the posttraumatic and dry-eye

groups) presented the microform, showing one of the

following: no epithelial defect, rug appearance of the

epithelium, punctate staining, pseudodendrites.

All of them complained about pain in the morning when

they woke up, seconds to minutes, and tearing, with no

visual loss.

The macroform cases presented :erosions, loose

epithelium, grey opacities, LIPCOF 2, lid wiper

epitheliopathy (1 case).

Symptoms were diverse : foreign body sensation,

burning to severe pain – hours to days, tearing and blurred

vision

Therapeutic contact lenses were fitted (without

anesthetic drops) in macroform cases, in 2 of them after

mechanical epithelium debridement. The desired fit was

moderate steep. Topical associated treatment was in all

cases preservative free lubricants. Lenses were used for

1 to 3 month, replaced monthly in office.

After TCL removal the patients were instructed

to use preservative free lubricants several times during

day-time and ointment at bed-time.

Complications In this cases we had NO infection, NO infiltrates,

NO neovascularisation.

Some of the cases showed mild lipid deposition,

due to the nature of the contact lens material.

2 cases needed refit in the second day because

discomfort persisted and epithelium did not seem to heal

fast enough. The steeper lens fitted showed better

performance.

In 5 cases (3 with corneal distrophies and 2 with

Dry eye syndrome) there were reccurences after 4to 6

month.

CONCLUSIONS

The success of this simple procedure depends on

the cause of the recurrent erosions, associated factors ,

type of TCL, long-term use, proper patient education. The

therapeutic lens should have high oxygen transmissibility,

low on-eye dehydration, good wettability, high lubricity.

The optimum fit for recurrent erosions is moderate steep.

Therapeutic bandage lenses are useful and

simple to use tools for treating recurrent corneal erosions

in any non-surgical ophthalmological unit

The eye specialist must be familiar with contact

lens fitting and aftercare

Education of the patient is very important in this

cases due to the unpredictable nature of the episodes

BIBLIOGRAPHY 1. Cernea Paul Tratat de oftalmologie Editura medicala

Bucuresti 2002 pg 304-322

2. Management of Ocular, Orbital and Adnexal Trauma,

ed Thomas C.Spoor and Frank A. Nesi Raven Press,

New York, 1988, Chapter 3 Corneal Trauma pag 51-

68

3. Reinecke Robert D Recurrent Corneal Erosions

Diagnostic and Management Ophthalmology Annual

1989 Raven Press New York, pg 65-93

4. Shah C, Raj CV, Foulks GN.,The evolution in

therapeutic contact lenses. Ophthalmol Clin North

Am. 2003 Mar;16(1):95-101

http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&Cmd=Search&Term=%22Shah%20C%22%5BAuthor%5D&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DiscoveryPanel.Pubmed_RVAbstractPlus

http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&Cmd=Search&Term=%22Raj%20CV%22%5BAuthor%5D&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DiscoveryPanel.Pubmed_RVAbstractPlus

http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&Cmd=Search&Term=%22Foulks%20GN%22%5BAuthor%5D&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DiscoveryPanel.Pubmed_RVAbstractPlus


AMT, vol II, nr. 1, 2010, pag. 67

5. Rubinstein MP., Applications of contact lens devices

in the management of corneal disease,Eye. 2003

Nov;17(8):872-6.

6. Coral –Ghanem C, Ghanem VC, Ghanem RC,

Therapeutic contact lenses and the advantages of high

Dk materials, Arq Bras Oftalmol 2008 Nov-Dec,

71(6Suppl):19-22

7. Pavan- Langston Deborah, Manual of Ocular

Diagnosis and Therapy Fifth Edition 2002 by

Lippincot Williams & Wilkins , Philadelphia USA pg

31-37, 67-130

http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&Cmd=Search&Term=%22Rubinstein%20MP%22%5BAuthor%5D&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DiscoveryPanel.Pubmed_RVAbstractPlus

javascript:AL_get(this,%20'jour',%20'Eye.');


AMT, vol II, nr. 1, 2010, pag. 68

PREZERVATIVES IMPACT OVER THE CORNEA

ELIGIA – MIRELA CIOBOTARU

Bistrita-Năsăud Hospital

Abstract: The cornea sensibility represent one of the most

important defense reflexes of the body. This is the modality

of keeping the functional and anatomical integrity of this

membrane, which has a special role in seeing proces.

Keywords: cornea, preservatives

Rezumat: Sensibilitatea corneei reprezinta unul dintre cele

mai importante reflexe de aparare ale organismului. Prin

aceasta se pastreaza integritatea anatomica si functionala

a acestei membrane cu un rol deosebit in realizarea

vederii.

Cuvinte cheie: cornee, conservanti

INTRODUCTIONCorneal anatomy

Anatomicaly, cornea is an optical, transparent

membrane of the former segment of the eye, which present

a series of stratify structures, different as origin,

construction and refraction index.

The medium diameter is about 12mm at human

people, the surface is of 1,3 cm, that means 7% from the

entire externe surface of the eye.

Cornea has a central thickness of about 0,53mm

with an increase of 50% around. The differences depend on

the histological particularities of the ratia between corneal

sections, kind,age and the normal curve.

Corneal histology

Histologicaly, cornea has 5 parallel sections:

- anterior epithelium cover by a thin liquid section – the

precorneal

film;

- Browman anterior limiting membrane;

- corneal stroma;

- posterior Descemet membrane;

- endothelium.

Up to the corneal epithelium surface, smooth and

shinny at uzual exam, but presenting microvillosity, there is

a precorneal film. Its thickness is about 7-9 microns and its

role is optical, nutritional and lubricant.

Eyedrops Eyedrops are sterile pharmaceutical products,

used in treatment and diagnose of eye sickness. They can

be solutions, emulsions or suspensions and are using like

drops – instillation – in the conjunctival bag. Conjunctiva,

beeing very vascularized, with a capilar system full in

anastamozis, make the conection with anterior ciliar

system, which means is the main place of absorbtion.

The drugs absorbtion in the eye depend of:

- solubility;

- ph;

- tampon system used;

- superficial pressure.

The eyedrops must realize some conditions, such

as :

- to be clear;

- to have the same osmotic pressure like the tear liquid;

- to provide the physical-chemical stability of active

principles and adjuvants;

- to have the same ph with the tears ( 7,4 – 7,8 );

- to have a good physiological tolerance;

- to be sterile;

- to be absolute pure.

The eye can support solutions with a ph between

6,5 – 9,5 because of neutral action of tears, which is a

tampon system, and of spontaneons weeping.

In ophthalmology the substances used for their

preservatives role must have some qualities:

- a longer spectrum of actions;

- a fast and long-term action;

- a good tolerance at used doses;

- to be compatible with joint substances and soluble;

- to be thermostabile and preservational;

- to have an anti-bacterial action in large limits of ph.

In the last few years there were published more

conclusions and chimical studies about preservatives,

especialy benzarkonium chloride, which suggest an

important role of these in topical toxicity of the eye drops,

when they are used for long-term treatments.

The detergents effects

Most of preservatives are basically detergents.

Quaternary ammonium salt has the biggest citotoxical

risk.It has a hydrophobic positive strong charged heed,

which permite the anchoring at membranes level. Ionical

interactions break-up the lipidic balance of plasma

membranes. In this way the preservatives can generate

canals of acces for ionic substances in intra and intercells

spaces. These effects are enough to make damages at

epithelial cells level and entering the fluid in excess at

stroma’s level to hydrate and make the corneal oedema.

The preservatives in higher concentrations can

produce cellular lisa,solving membranes by the a detergent

effect. In small concentrations may prevent intercells


AMT, vol II, nr. 1, 2010, pag. 69

interactions, which are vital for cells life.

Grounds for concern

The prolonged use of eye drops containing

preservatives can causes allergic or inflammatory reactions,

either immediate or delayed:

- burnings;

- foreign body sensation;

- hyperaemia;

- superficial punctuate keratitis, especially in the lower

part of the cornea.

The toxicity of ophthalmic solutions which

content preservatives may generate modifications of tear

film, damages of corneal-conjunctival epithelium and also

a higher permeability on epithelial level.

It can be noticed a chronical inflammatory

reaction and conjunctival fibrosis, sometime extended

through trabecular level, at patients under long time

treatment, in addition with antiglaucoma drugs.

Inflammation and the tear film The tear film has a protection and nutritional role,

most important for a healthy eye surface. The interruption

of the lipidic component, low stability and the solubility are

the primare adverse effects induced by using preservatives

products, especially those which contents quaternary

ammonium salt.

The “detergent” effect can produce a faster

evaporation of the tear film and also an aggravation of a

before existing sicca sindrom.

Nuzzi ed al. shows that, using for 3 month of

benzalkonium chloride to patients without ocular diseases,

can produce ocular and conjunctival changes with the same

intensity as to the open ungle glaucoma’s patients, beeing

under long-term treatment. Instillation of one single drops,

with 0,01% concentration, of benzalkonium chloride to

healthy pacients, decrease the half-timing of the tear film.

Clinical observations about corneal toxicity

The toxical keratitis caused by the detergents have

been describes in different situations - at the contact lenses

users or those with dry eye syndrome, either after surgery.

The long-term exposure with products which

content preservatives, may be extremely dangerous, getting

to:

- loss of epithelium;

- oedema at stroma’s level;

- infiltrations and corneal opacity.

The biomicroscop exam shows the appearance of

epithelial erosions and vascularizations at the inferior level

of cornea.

The symptoms are improved when the treatment

is stoped, or the contact lenses are getting away or if there

are used ophthalmic solutions without preservatives.

Probably that behind a long-term treatment which

content preservatives, these interfere with the cells

metabolism, producing toxic effects getting to the death of

the cells, premature desquamates of epithelial cells, rupture

of stromal keratocytes and possibly degeneration of

endothelial cells, and lead to marked ulcerative

keratopathies.

Kilt report the case of a woman aged 46

instilling,for a dry eye syndrome, a solution containing

benzalkonium every two hours. She developed a

superficials keratitis. The symptoms worsened, a

preservative free treatment was substituted, whereupon the

keratopathy regressed after one week.

During general anaesthesia,the cornea is

especially sensitive to reduced tear production and ocular

lubricants are after prescribed.

Maneke report a severe corneal aggression with

conjunctival hyperaemia, photophobia, reduction of visual

acuity, in a man aged 47, who had received an ocular

lubricant conteining 0,5% chlorobutanol,a preservative

normally less toxic than benzalkonium chloride.

Fluorescein staining showed de-epithelialised areas.

Symtoms were alleviated after 3 days treatment with AB,

anti-inflammatory drugs and artificial tears, preservative-

free. Visual acuity reverted to normal after 2 weeks.

To avoid a possible contamination which will

increase the microbian flora, allmost all the eyedrops of

ophthalmic use contains preservatives, bactericides,

bacteriostatics and/or antifungicides, compatible with the

other solutions components.

The antiseptical property of the preservatives

depend on the non-specify biological activity which result

on solubility or membranes, an increase of ionical

permeability and/or the cells methabolic inhibity. Using

these substances in ophthalmic solutions is risky. The use

of preserved eyedrops is not free of risks, especially for the

conjunctival-corneal surface.

Although the ophthalmic use solutions were

preliminary tested, both clinic and paraclinic, for proving

the low degree of toxicity, there were patients which

accused of stinging and burning, dry eye syndrome and

discomfort.

The dry eye syndrome

In this syndrome, the eyedrops preservatives-free

are must efficient in keeping the affected corneal

epithelium integrity.

Goblet made a comparative study on 56 patients

which have got keratoconjunctivita sicca. The treatment

with preservative-free solutions based on

carboximetilceluloza conducted to a sensitive improvement

of the functional simphtoms of superficial punctuate

keratitis and squamate metaplazy, in comparison with the

patients treated with preservatives artificials tears.

These results have confirmed by Smith in a study

on 30 patients with dry eye syndrome, inefficient treated

with solutions having preservatives, were treated with

preservatives from eyedrops in one eye, in the other

remaining the same drops. After 2 weeks, 63% of patients

declared they prefer the preservatives free eyedrops, having

a considerable improvement of the symptomes.In the eye

treated with preservatives eyedrops there are no

modifications.

CONCLUSIONS

- the eyedrops used in ophthalmology for treatment and

diagnosis contain, beside the active substance, one

preservative with bactericide and fungicide role, many

times responsable of alergical reactions.


AMT, vol II, nr. 1, 2010, pag. 70

- the sensibility for preservatives is growing up because

there are inside both ophthalmic used solutions and

usual products, like: soaps, cosmetics, dezinfectants.

- although, considering the occurrence of adverse effects

(stinging, burning, hyperaemia, ocular pruritus), it is

advisable to restrict the use of preserved eyedrops and

to replace them with preservative-free alternatives,

these being most efficient in keeping the corneal

epithelium integrity.

BIBLIOGRAPHY 1. Prof. Christophe Baudouin, Quinze-Vingts National

Hospital Centre for Ophthalmology, Paris, France: 10

years of preservative-free eyedrops.

2. Tripathi, B.J., Tripathi, R.C., and Kolli, S.P.

Cytotoxicity of ophthalmic preservatives on human

corneal epithelium. Lens Eye Toxic Res.

3. Gasset AR. Benzalkonium chloride toxicity to the

human cornea.Am.J. Ophthalmol.1987;

4. Garcher C, Bron A, Baudouin C, Bildstein L, Bara J.

New method for studing mucus changes in tears.

Ophthalmol. 1998;

5. Liesegang TJ. Conjunctival changes associated with

glaucoma therapy; implications for the external disease

consultant and the treatment of glaucoma. Cornea.

1998;

6. Liu H, Routley I, Teichmann KD, Toxic endothelial

cell destruction from intraocular benzalkonium

chloride. J. Cataract Refract Surg.

7. Manecke GR Jr, Tannenbaum DP, McCoy BE. Severe

bilateral corneal injury attributed to a preservative-

containing eye lubricant. Anesthesiology. 2000;

8. Wilson WS, Duncan AJ, Jay JL, Effect of

benzalkonium chloride on the stability of the

precorneal tear film in rabbit and man.

9. Zabel RW, Mintsioulis C, MacDonald IM, Valberg J,

Tuft SJ, Corneal toxic changes after cataract

extraction. 1989;

10. Robert, P.Y, and Adenis, J.P. Comparative review of

topical ophthalmic antibacterial preparations. 2001;

11. Lass, J.H., Mack, R.J., Imperia, P.S., Mallick, and

Lazarus, In vitro analysis ofaminoglycoside corneal

epithelial toxicity. 1989.


AMT, vol II, nr. 1, 2010, pag. 71

OUR EXPERIENCE WITH THE ALLEGRETTO

WAVELIGHT EYE Q 400 HZ EXCIMER LASER IN

PATIENTS WITH HYPEROPIA AND HYPEROPIC

ASTIGMATISM

MONICA GAVRIŞ, GENOVEVA OLARU, DIANA POPA, L. LEVAI

LASER OPTISAN & OPTISAN 2002 SRL Ophthalmologic Clinic Cluj-Napoca

Abstract: Allegretto Wave Eye Q 400 Hz excimer laser is

the most rapid laser system available in the correction of

the sight that allows the correction with 1 diopter in 2

seconds.The aim of the study is to evaluate the efficiency

and safety of the excimer laser Allegretto Wave Eye Q

400 Hz in the correction of the hypermetropi and

hypermetropic astigmatism. A prospective study has been

realised on 12 patients, respectively 23 eyes with

hypermetropi and hypermetropic astigmatism. The

patients’s ages are of 20 to 58 years. The functional

results have been evaluated in one week, one month, two

months and 6 months postsurgery. The surgical

correction of the hypermetropi and hypermetropic

astigmatism remains a challenge in the refractive

surgery. WaveLight Allegretto Eye Q 400 Hz excimer

laser represents a solution to the reduction of the

dioptries in patients with hypermetropi and

hypermetropic astigmatism until 6 dioptries, if the

patient’s selection is well done and the patient has no

great expectations.

Keywords: Allegretto Wave Eye Q 400 Hz laser excimer

Rezumat: Laserul excimer Allegretto Wave Eye Q 400 Hz

este cel mai rapid sistem laser disponibil pentru corectia

vederii ce permite corecţia de 1 dioptrie in 2 secunde.

Scopul studiului este de a evalua eficacitatea şi siguranţa

laserului excimer Allegretto Wave Eye Q 400 Hz în

corecţia hipermetropiei şi astigmatismului hipermetropic.

A fost realizat un studiu prospectiv pe 12 pacienţi,

respectiv 23 ochi cu hipermetropie si astigmatism

hipermetropic. Vârstele pacienţilor au fost cuprinse între

20+58 ani. Rezultatele funcţionale au fost evaluate la 1

săptămână, 1 lună, 2 luni şi la 6 luni postoperator.

Corecţia chirurgicală a hipermetropiei şi astigmatismului

hipermetropic rămâne o provocare în domeniul chirurgiei

refractive. Laserul excimer WaveLight Allegretto Eye Q

400 Hz reprezintă o soluţie de reducere a dioptriilor la

pacienţii cu hipermetropie şi astigmatism hipermetropic

pană la 6 D, dacă selecţia pacienţilor este bine făcută şi

dacă pacientul nu are aşteptări exagerate.

Cuvinte cheie: laserul excimer Allegretto Wave Eye Q

400 Hz,

INTRODUCERE

WaveLight was the first to introduce in the USA

the high speed Laser for vision correction. Allegretto

Wave Eye Q 400 Hz excimer laser is the fastest laser

available today. It corrects 1 diopter in 2 seconds. The

high speed Eye-Tracker follows eye movements,

checking the eye’s position 400 times every second

providing an exact placement of every laser beam on the

cornea. The ultra-fine profile of the laser (0.95nm) sculpts

the corneal surface with utmost precision.(1)

SCOPUL LUCRĂRII

To evaluate the efficacy and safety of the

Allegretto Wave Eye Q 400 Hz excimer laser for the

correction of hyperopia and hyperopic astigmatism.

MATERIAL ŞI METODĂ

Prospective clinical study on 12 patients

(23eyes), with hyperopia and hyperopic astigmatism who

underwent laser vision correction using Lasik technique

and the Wave Light Allegretto Eye Q 400Hz excimer

laser.

Patients had ages ranging between 20 and 58

years.

Every patient underwent a meticulous

preoperative protocol consisting of:

Best corrected visual acuity (BCVA)

Cycloplegic refraction

Anterior and posterior segment exam

IOP

Keratometry

Pachymetry

Corneal topography

Results were evaluated 1 week, 1, 2, 6 months

postoperatively.

Preoperative BCVA ranged between 0.4 and 5/5.

Following cycloplegia, hyperopia ranged

between 2.75 and 7.50 D and astigmatism ranged between

0 and 6 D, 11 eyes presenting hyperopia and 12 hyperopic

astigmatism.

Anterior and posterior segments were normal, 1

patient presenting convergent squint.

Keratometry, Pachymetry, Corneal topography

were executed using the Oculyzer corneal topographer.

Based on Pentacam technology that uses Scheimpflug

three-dimensional imaging, the Oculyzer provides:

Corneal topography

Keratoconus detection and grading


AMT, vol II, nr. 1, 2010, pag. 72

Complete 3D anterior chamber analysis

Lens analysis

Oculink software for costumized laser correction (2)

Corneal topography excluded keratoconus, all

cases of astigmatism being with the rule.

Keratometry readings rangend between 40 and

46 D.

Pachymetry ranged between 507 and 640 µm.

Surgical technique – LASIK

130 µm flap made with Rondo microkeratome and

8.5mm suction ring

6.5 mm optical zone

BSS rinsing of the ablation surface

Flap adjustment + TCL

Postoperative treatment with antibiotic +

dexamethazone and artificial tears.

RESULTS

UCVA was better than 0.5 in 9 patients and

lower than 0.5 in 1 patient. 2 patients had BCVA over 0.5.

9 out of 12 patients gained estimated diopter reduction,

the remaining presented 1.5-2 D of residue. Patients with

1.5-2 D of residue presented more than 6 D

preoperatively.

The patient with convergent squint, presented

orthoposition postoperatively.

None of the patients lost any line on Snellen

chart, one patient with hyperopic astigmatism gained 3

lines.

All patients were satisfied.

Intraoperative complications did not exist. The

flap was clean, with smooth edges, well positioned,

without interface debris after 2 and 7 days

postoperatively.

Postoperative complications occurred in 2 cases:

- In 1 case, margin sclerosis of the flap occurred, one

month postoperatively, which resolved under anti-

inflammatory treatment.

- In 1 case, epithelial ingrowth appeared 0.5 mm under

the temporal margin one month postoperatively. The

affected area was rinsed and under topical cortisone

the evolution was favorable.

DISCUSSION

A study conducted on 120 patients with

hyperopia and hyperopic astigmatism, followed 12

months postoperatively, revealed a stable refraction of

+/- 0.50 D variation from the target refraction in 92 % and

71% of patient respectively, according to the degree of

refractive error.(3)

Another study conducted in Spain on hyperopic

patients up to 6.25D revealed that 70% of patients with

hyperopia under 3 D and 63 % over 3 D had a +/-0.50 D

postoperative refraction. Approximately 20% of patients

needed a second intervention.(4)

In our study postoperative refraction was stable

1, 2 months postoperatively. Four patients had stable

refraction 6 months postoperatively.

VA was good in all the patients, no one

complaining of haze or night vision difficulties.

CONCLUSION

1. Correction of hyperopia and hyperopic astigmatism

remains a challenge in the treatment of refractive

surgery.

2. The possibility of regression remains a problem in

this field because of the filling of the ablated area due

to natural or hyperplasic healing of the cornea.

3. WaveLight Allegretto Eye Q 400 Hz excimer laser is

a trustworthty tool in diopter reduction in patients

with hyperopia and hyperopic astigmatism up to 6 D,

if the patient is well sellected an doesn’t have

exagerrated expectations.

BIBLIOGRAFIE 1. http://www.eagleeyecentre.com.sg/allegretto_wave.ht

ml

2. http://www.wavelight.com

3. A. John Kanellopoulos, MD; Joseph Conway, MD;

Lawrence H. Pe, MD and Ian F. Comaish, MA, BM,

BCh, FRCOphth. Original Articles:LASIK for

Hyperopia With the WaveLight Excimer Laser.

Journal of Refractive Surgery Vol. 22 No. 1

January 2006

4. Arun C Gulani, MD. Hyperopia, Lasik. emedicine

Nov 24, 2008

5. LASIK safe and effective for treating hyperopia,

study says. www.lasiksurgerynews.com, JUL 20,

2009


AMT, vol II, nr. 1, 2010, pag. 73

IS MONOVISION A SOLUTION IN CORRECTING

PRESBYOPIA?

ADRIANA STANILĂ

“Lucian Blaga”University Sibiu, Ocular surface research center

Abstract: Presbiopya is a phisiological condition which

affects every person either emetrop, myop, hyperop or

astigmat. The optical correction of presbyopia may be

done using: glases (mono, bi, tri, multifocal lens); bifocal

or multifocal contact lens. The optic correction can be

done monocular or binocular. Can monovision be a

solution for correction of the presbiopia?

Keywords: presbyopia, contat lenses, monovision

Rezumat: Prezbiopia este o tulburare fiziologică a

acomodaţiei ce apare la toţi indivizii, fie ei emetropi,

hipermetropi, miopi sau astigmaţi. Corecţia prezbiopiei

se poate face optic cu: lentile aeriene (mono, bi, tri sau

multifocale); lentile de contact bifocale sau multifocale.

Corecţia optică se poate face monocular sau binocular.

Este oare monovision o soluţie în corecţia prezbiopiei?

Cuvinte cheie: prezbiopia, lentile de contact, monovision

INTRODUCERE

Presbyopia has been described by Michaels D. as

“an irreversible optical failure, an unexplained

evolutionary blunder that comes as a psychological

shock.“

Presbyopia (Greek word "presbys" - πρέσβυς),

meaning "old man" or "elder", with Latin root "-opia",

meaning "eye") describes the condition where the eye

exhibits a progressively diminished ability to focus on

near objects with age. Presbyopia is one of the earliest

signs of aging. Age is the major risk factor for presbyopia

and primitive cataract - the most common diseases of the

lens.

Presbyopia's specific mechanisms are not known

for sure, however, the research evidence most strongly

supports a loss of elasticity of the crystalline lens,

although changes in the lens's curvature from continual

growth and loss of power of the ciliary muscles (the

muscles that bend and straighten the lens) have also been

postulated as its cause. Although there are still

structurally and functionally uncertainties about the

ciliary muscle, it is certain that this is the engine of the

accommodation mechanism.

Currently presbyopia is explained by the

hypothesis of Helmholtz which says that for distance

vision the ciliary muscle relaxes and the zonula becomes

tensioned. When the eye accommodates the ciliary muscle

contracts, decreasing the tension of the zonula. Lowering

the zonular tension in the presence of an elastic lens

capsule is followed by lowering of the equatorial diameter

and of the radius of the lens both sides curvature s and

increasing the central thickness of the lens.

http://en.wikipedia.org/wiki/Lens_%28vision%29

http://en.wikipedia.org/wiki/Ciliary_muscle


AMT, vol II, nr. 1, 2010, pag. 74

Presbyopia can be corrected with glasses or

contact lenses. In some cases, the addition of bifocals to

an existing lens prescription is enough. As the ability to

focus up close worsens, the prescription needs to be

changed. With the use of contact lenses, some people

choose to correct one eye for near and one eye for far

vision. This is called "monovision" and eliminates the

need for bifocals or reading glasses, but it can affect depth

perception.

There are also newer contact lenses that can

correct for both near and far vision with the same lens –

multifocal contact lenses. New surgical procedures can

also provide solutions for those who do not want to wear

glasses or contacts.

Spectacle correction of presbyopia

- Separate reading spectacles: normal or ‘half eye’

frames

- Bifocal/trifocal lenses: two or three zones of

correction (distance / near or distance / near /

intermediate)

- Progressive / Varifocal: Gradual change in power

from distance to near (all zones in focus)

Contact lens options

- Simultaneous vision: concentric bifocal c.l., aspheric

(progressive) c.l.

- Alternating vision: translating design

- Monovision

Surgical treatments of presbyopia

- Surgical reversal of presbyopia – scleral expansion

bands (SEB) placed below the surface of the eye’s

sclera

- Anterior ciliary sclerotomy – 8 incisions in a radial

pattern across the surface of the sclera

- Laser presbyopia reversal – simillar to anterior ciliary

sclerotomy

- Photophaco reduction – uses a laser to create cavities

in the lens and reduce its size

- Lens replacement

Monovision represents the art of science of

fitting contact lenses on a patient with presbyopia: one

eye is fit with a distance lens (if needed) and the other eye

is fit with a near lens. When we look into the distance we

are using the vision from the dominant eye. Our brain

pays more attention to the visual information received

from the dominant eye.

Monovision works because the brain is tricked

into thinking that the CL actually is a part of the natural

eye. Monovision is a blend of near and distance vision,

ideal for people with an active lifestyle.

Usualy request a brief period of adaptation as the

brain “learns” to see with the eye best suited for the task.

The process of adaptation to monovision usually takes

about 1 – 2 weeks when the brain begins to use the eyes

in monovision manner and the person becomes unware

which eye is focused at near and which at distance.

Reading glasses may occasionally still be required for

some near activities.

The most common method of achieving

monovision is through the use of CLs. With glasses, the

difference in the thickness of the glass between the two

eyes can cause bothersome symptoms. Monovision can

also be obtained by surgical means: excimer laser

refractive surgery – LASIK or PRK. Last but not least

monovision can be a result of cataract surgery, using IOL

in one eye for near and a distance focused lens in the

other.

10 -15% of people who try monovision do not

adapt because of eyestrain or headaches or mild loss of

stereo vision. Usually is better to prescribe monovision

with enough correction to allow good intermediate

distance viewing, for example for reading larger prints

like a dinner menu. For very fine print or small objects,

monovision patients may still need the help of readingt

glasses.

Correcting presbyopia with contact lenses can be

both rewarding and challenging. While somewhat

dependent on the lens type chosen and patient-related

factors, the degree of difficulty encountered when

correcting presbyopia with contact lenses can sometimes

approach that of other, technically more demanding, tasks

such as astigmatism and keratoconus. The nature and

significance of presbyopia itself may need to be explained

clearly to the patient before proceeding to detail their

correction options (i.e.contact lenses and spectacles)

along with the advantages and disadvantages of each. The

correction of presbyopia is more about selecting a lens

type/correction mode that will provide acceptable vision

at both distance and near, often being something of a

compromise at one distance at least. Monovision provides

the simplest method of correcting both distance and near

vision with contact lenses. A more complex monovision

approach uses a bifocal lens in one eye and a single vision

contact lens in the other, i.e. so-called modified

monovision. Usually, the single vision lens is used to

correct the patient’s vision for their most critical viewing

distance, i.e. distance or near. Correction of young

presbyops is better tolerated with multifocal contact

lenses in both eyes (simultaneous vision). Success rate

depends on: previous correction, occupation, motivation.

Presbyops over 50 years old – in our opinion – are the

best candidates for monovision correction – correcting the


AMT, vol II, nr. 1, 2010, pag. 75

dominant eye for distance and the non dominant eye with

a multifocal lens.

BIBLIOGRAFIE

1. Michaels DD., Visual optics and refraction: a clinical

approach, 3rd ed. St. Louis

2. Stanila Adriana, ABC in oftalmologie, Ed. Tribuna

Sibiu, 1997

3. Stanila Adriana, Cristalinul, Ed. Polsib Sibiu, 2001

4. Judith Lee, Gretchyn Bailey, Presbyopia

5. Khiun F. Tija, Cataract & Refracting Surgery:

Monovision: A Multitude of Options and Opinions,

October 2009, Volume 4, No.9

6. American Optometric Association, Monovision, 3

Nov 2007

7. Sherman Winston Reeves, Monovision

8. Robert Abel, The Eye Care Revolution: Prevent and

Reverse Common Vision Problems, Kensington

Books, 2004

9. Garcia Serrano, JL; Lopez Raya; Mylonopoulos

Caripidis, Variables related to the first presbyopia

correction, Archivos de la Sociedad Espaniola de

Oftalmologia

10. Eg, Free Eye Exercises for better vision Malecaze,

FJ; Gazagne; Tarroux; Gorrand, Scleral expansion

bands for presbyopia


AMT, vol II, nr. 1, 2010, pag. 76

THE USE OF HUMAN AMNIOTIC MEMBRANE IN

OCULAR SURFACE DISEASES

ADRIANA STĂNILA1, DIANA MIHU2, T. PRIPOREANU3, ANDREEA BOTEZAN4,

I. COSTACHE5, D. STĂNILĂ6

1,3,6 “Lucian Blaga” University of Sibiu, 2,4 Emergency Hospital Sibiu, 5 Ocular Surface Research Center Sibiu

Abstract: This study presents various methods of possible

use of the human amniotic membrane in the pathology of

the eye surface. The study lot consists of 39 cases, with

different pathologies, that required human amniotic

membrane (HAM) transplant. The results indicate that

HAM significantly decreases the ocular symptoms, is an

inexpensive and reiterative solution and has a very good

tectonic effect in the cornean perforations, utilised

correctly is an inovative solution in the treatment of the

ocular surface diseases.

Keywords: amniotic membrane, pterygium, bullous

keratopathy, corneo-conjunctival burns, exposure

keratopathy, corneal ulcer

Rezumat: Lucrarea prezintă diferite modalităţi de

folosire a membranei amniotice umane în patologia

suprafeţei oculare. Lotul de studiu este format din 39

cazuri, cu diferite patologii, care au necesitat transplant

de membrană amniotică umană (MAU). Rezultatele

studiului indică faptul că MAU reduce semnificativ

simptomele oculare, este o soluţie ieftină şi repetitivă, are

un efect tectonic bun în perforaţiile corneene, utilizată

correct este o soluţie inovatoare pentru tratamentul

afecţiunilor suprafeţei oculare

Cuvinte cheie: membrană amnitotică umană, pterigion,

keratopatie edemato-buloasă, arsuri corneo-

conjunctivale, keratopatie de expunere, ulcer cornean.

INTRODUCTION

The amniotic membrane has a total thickness of

0.5 mm and is composed of three layers; one layer of

cubic epithelial cells, basement membrane with a

thickness of about 200 – 300 nm and an avascular stroma

made out of a collagen network with few fibroblasts.

The properties of human amniotic membrane

(HAM) that made it fit to be used are:

it stimulates reepithelization by modulating the

epidermic growth factoe, keratocite growth factor,

fifbroblast growth factor and α and β growth factor.

antiinflamatory effect by modulating some

proinflamatory citokines (TGFα, TGF β, IL 1α and

1β, keratocite growth factor etc.)

antibacterial properties

imunomodulating effect (incomplete expresion of

HLA-A, B, DR antigenes), which makes the use of

imunosupressors unnecessary.

inhibits vascular endothelium growth and thus

prevents neovascularization

inhibits scar formatin by supressing miofibroblast

diferentiation to fibroblasts and the production of

extracellular matrix.

The indications of HAU in the ocualr surface

pathology are:

Persistent corneal epithelial defects

Conjunctival defects

Surgical correction of simblefaron

Burns

Pterygium recurrence in combination with limbic

cells transplant.

Ex-vivo expansion of limbic stem cells

The techniques for using the HAM are:

1. PATCH (OVERLAY): the HAM is sutured at the

episclera, circular above the epithelial or stromal

defect, while the margins of the defect remain under

the HAM.

2. GRAFT (INLAY – one or more layers): the HAM is

sutured at the ulceration site and the corneal

epithelium regenerates above it. HAM functions as a

basement membrane, is integrated in the cornea and

remains there for a few months. It is important for the

epithelium to be removed around the ulceration and

for tha HAM to be sutured in the opaque stroma. If

the ulceration is deep, the HAM may be applied in

more layers, and we can suture only the one on top.

3. SANDWICH: combines the previous two techniques.

This technique has a high success rate and a low

recurrence incidence.

AIM OF STUDY

We want to show different modalities of using

the human amniotic membrane in several ocular surface

diseases.


In 2003-2009 we used the HAM transplant in 39

cases with different pathologies:

Bullous keratopathy, 12 cases

Pterygium, 10 cases

Corneo-conjunctival burns, 4 cases

Exposure keratopathy, 4 cases

Neurotophic keratopathy, 2 cases


AMT, vol II, nr. 1, 2010, pag. 77

Perforated corneal ulcer, 3 cases

Herpetic keratitis, 2 cases

The surgery is made in topical and/ or

retrobulbar anestethesia. The HAM is placed with the

epithelial part on top and is sutured with separate suture

points if the suture is cornean, or continuous suture if it is

limbic. After surgery we apply a theraputic contact lens to

fixate the membrane and to delay its resorbtion. The

suture points are removed after at least one month in order

to prevent angiogenesis.

RESULTS

The patients with bulous keratopathy following

cataract surgery by facoemulsification present with

symptom like ocular pain, foreign body sensation,

photophobia, tearing. After doin the HAM transpalnt

these symptoms are reduced gradually.

Figure no. 1. Fist day postop

Figure no. 2. 1 month postop

Figure no. 3. 6 months postop

In large pterygiums and aggressive recurrences

we thought necessary the HAM transplant together with a

theraputical contact lens after surgical excision of the

pterygium.

Figure no. 4. Pterygium preop

Figure no. 5. 7th day postop (HAM+TCL)

Figure no. 6. 6 weeks postop

We used the HAM transplant in old corneo-

cunjunctival burns with simblefaron formation with good

results.

Figure no. 7. Old corneo-conjunctival burn


AMT, vol II, nr. 1, 2010, pag. 78

Figure no. 8 HAM transplant

Figure no. 9. 14th day postop

CONCLUSIONS

In bullous keratopathies the amniotic membrane

transplant reduces the symptoms (pain, foreign

body sensation, photophobia, tearing).

Although the transplant of the amniotic membrane

can not be considered the final solution in bullous

ketatopathy, it has great benefits being a cheap and

repetitive option for these patients, before doing the

perforating keratoplasty.

Using amniotic membrane transplant combined with

TCL in the treatment of large pterygiums or

agressive recurrences is a promising option in the

management of this unpleasant corneal disease.

Amniotic membrane transplant associated with TCL

provides good tectonic effects in corneal

perforations.

Fresh HAM correctly used and fixed is an innovating

solution for treating ocular surface diseases.

BIBLIOGRAFIE 1. Ozkurt YB, Kocams O, Comez A, Uslu B, Dokan

OK (2009). Treatment of Primary Pterygium.

Optometry and Vision Science.

2. Jain, A MD; Bansal, R MD; Sukhija, J MD (2008).

Human Amniotic Membrane Transplantation With

Fibrin Glue in Management of Primary Pterygia: A

New Tuck-in Technique. Cornea, 27, 94-99.

3. Muller M, Meltendorf C, Mirshashi A, Kohnen

T(2009). Use of multilayer amniotic membrane as

first therapy for penetrating corneal ulcers. Klinische

Montsblatter fur Augenheilkunde, 8, 640-4.

4. Resch M, Resch B, Imre L, Nemeth J, Csanyi E

(2009). Permeability of human amniotic membrane to

ofloxacin in vitro. Investigative ophthalmology.

5. Resch M, Schlotzer U, Hofmann C, Sauer R, Kruse

F, Beckmann M, Seitz (2009). Integration patterns of

cryopreserved amniotic membranes into the human

cornea. Ophthalmology, 11, 1927-35.

6. Miranda-Rollon, Sentieri A, Martinez R, Junceda-

Moreno C (2009). Treatment with amniotic

membrane in keratolysis secondary to adult

gonococcal keratoconjunctivitis.Archivos de la

Sociedad Espanola de Oftalmologia, 3,155-7.

7. Kheirkhah A, Johnson DA, Paranjpe DR, Raju V,

Casaa V, Tseng SC (2009). Temporary sutureless

amniotic membrane patch for acute alkaline burns.

Archives of ophthalmology, 8, 1059-66.

8. Barequet IS, Habot-Wilner Z, Keller N, Smollan G,

Ziv H, Belkin M, Rosner M (2008). Effect of

amniotic membrane transplantation on the healing of

bacterial keratitis. Investigative Ophthalmology &

visual science, 49(1), 163-7.

9. Dekaris I, Gabrić N, (2009). Preparation and

preservation of amniotic membrane. Developments in

Ophthalmology, 43, 97-104.

10. Kitagawa K, Yanagisawa S, Watanabe K, Yunoki T,

Hayashi A, Okabe M, Nikaido T (2009). A hyperdry

amniotic membrane patch using a tissue adhesive for

corneal perforations and bleb leaks. American

Journal of Ophthalmology, 148(3),383-9.

11. Ozer A, Yildirim N, Erol N, Yurdakul S (2009).

Long-term results of bare sclera, limbal-conjunctival

autograft and amniotic membrane graft techniques in

primary pterygium excisions. Ophthalmologica,

223(4), 269-73.

12. Yoon KC, Im SK, Kim JC, Yoon KW, Choi SK

(2009). Prognosis of paraquat-induced ocular surface

injury: therapeutic effect of amniotic membrane

transplantation. Cornea, 28(5), 520-3.


AMT, vol II, nr. 1, 2010, pag. 79

OSMOPROTECTION - A NEW APPROACH TO

TREATING DRY EYE

GABRIELA OPREA

Bucuresti

Abstract: Dry eye disease is characterized by a

compromised tear film (cracked, desiccated appearance)

and cells that are dehydrated and out of balance. Many

artificial tears products provide only a single mode of

protection against dry eye and simply supplement a

compromised tear film. Osmoprotection is a new

approach to treating dry eye by providing cellular

protection against the effects of hypertonicity.

Keywords: osmoprotection, lacrimal film, artificial tears

Rezumat: Patologia ochiului uscat este caracterizată

printr-un film lacrimal compromis, întrerupt şi cu celulele

epiteliale deshidratate şi în dezechilibru. Majoritatea

produselor de tip lacrimi artificiale oferă doar un singur

mod de protecţie împotriva uscării ochiului şi acesta este

simpla suplimentare a filmului lacrimal compromis.

Osmoprotecţia este o nouă abordare în tratamentul

ochiului uscat, o abordare ce asigură protecţia celulelor

epiteliale corneene împotriva efectelor hipertonicităţii.

Cuvinte cheie: osmoprotectie, film lacrimal, lacrimi

artificiale

INTRODUCERE

Put simply, in a healthy ocular surface, the tear

film is uncompromised, the epithelial cells are hydrated

and in osmotic balance, and the tear film provides

maximum comfort.

Since there is no blood supply to the ocular

surface, natural healthy tears are essential for maintaining

optimal ocular health. Besides providing a proper

chemical environment at the ocular surface, the tear film

also serves a number of important functions in

maintaining the overall health of the eye, including:

ocular surface comfort , protection from infection,

nutrition, wound healing, and cell growth , optical clarity

and refractive power.

In order to perform these critical functions,

normal healthy tears contain a complex and balanced

mixture of electrolytes, proteins, and mucins. These key

elements are found in the 2 components that make up the

tear film: the lipid layer and the aqueous/mucin gel.

Dry eye disease is characterized by a

compromised tear film (cracked, desiccated appearance)

and cells that are dehydrated and out of balance.

In dry eye, underlying changes to ocular health

and environment can adversely affect both the quantity

and quality of the tear film. This results in an unbalanced

tear film that can no longer provide sufficient

nourishment or protection to the ocular surface. In turn,

this may lead to permanent damage to the corneal

epithelium cells as well as to the corneal nerve fibers that

trigger tear secretion.

In summary, the tear film in dry eye is thinner

and more unstable than healthy tear film, and the balance

of electrolytes, proteins, and mucins has been upset.

Symptoms vary from patient to patient, but most

commonly they include itching; a sandy, gritty feeling;

burning; sensitivity to bright lightning and sunshine;

foreign-body sensation; irritation; pain; blurred vision;

and contact lens intolerance. In extreme cases, dry eye

disease can also lead to permanent visual impairment.

Most artificial tears contain similar ingredients:

lubricants, water, electrolytes, buffers, and a preservative.

However, they differ in: the type of lubricant

(carboxymethylcellulose (CMC), polyvinyl alcohol,

polyethylene glycol, etc), chemical properties (unique

buffers, osmotic agents, etc), type of preservative,

viscosity.

Although all currently available artificial tear

solutions simply moisturize the eye, the different artificial

tears utilize different approaches to achieve this goal.

These mechanisms include tears that:

- Counteract hypertonicity: hypotonic solutions may be

used to provide temporary relief by increasing water

content

- Contain oil: improve lipid layer of tear film to

prevent tear evaporation

- Increase retention time: work by increasing viscosity

or use ingredients with bioadhesive properties to

increase the retention of tears on the ocular surface

Compatible solutes: small, non-ionic organic

compounds that build osmotic strength intracellularly

without damaging proteins

When tear film is healthy, it maintains a constant

osmolarity of about 295 to 305 mOsm/L. In dry eye,

however, the quantity of water in the tear film is

decreased, perhaps as the result of high evaporation or

because sufficient water is not produced in the first place.

Because there is less water in the tear film, the

concentration of solutes such as sodium and potassium

increases. This raises the osmolarity and upsets the


AMT, vol II, nr. 1, 2010, pag. 80

isotonic balance that had existed between the tear film

and the ocular epithelial cells. When cells are dehydrated

and out of balance, the tear film becomes hypertonic.

The aqueous solution in the tear film is

hypertonic in comparison with the aqueous solution

within the ocular epithelial cells. In order to restore the

isotonic balance, water flows by osmosis out of the ocular

epithelial cells. When this happens, the osmolarity of the

corneal epithelial cells rises beyond accepted levels and

they can cease to function properly.

Many artificial tears products provide only a

single mode of protection against dry eye and simply

supplement a compromised tear film. Their primary

mechanism of action neutralizes the hypertonic state of

the tear film by flooding the ocular surface with moisture.

In other words, these agents treat only the tear film

component of dry eye conditions. This modality provides

only temporary, short-acting symptom relief.

A hypertonic tear film causes cells to desiccate,

or lose cell water and volume.

Regulatory volume increase occurs as cells take

up salt from the environment to try to return to a normal

volume. This results in an electrolyte imbalance. The

electrolyte imbalance, if not addressed by compatible

solutes, results in cell damage. If the electrolyte

imbalance is addressed, by accumulation of compatible

solutes, the result is osmoprotection.

L-carnithine and erithrytol were identified,

separated or in combination, as being protective against

cellular stress activation at the level of epithelial corneal

cells in hypertonic environment.

Osmoprotection is a new approach to treating

dry eye by providing cellular protection against the effects

of hypertonicity.

An advanced tear consists of a balanced tear film

and healthy corneal epithelial cells.

A dual-action approach provides: hydration and

lubrication to the epithelial surface, a protective action

against the damaging effects of dry eye on and below the

corneal surface.

BIBLIOGRAFIE 1. “Effects of Osmoprotectants on Hyperosmolar Stress

in Cultured Human Corneal Epithelial Cells” Rosa

M.Corrales, MD, Lihui Luo, MD, Eliseu Y. Chang,

MD, and Stephen C. Pflugfelder, MD


AMT, vol II, nr. 1, 2010, pag. 81

A NEW APPROACH OF THE DRY EYE SYNDROME;

THE TEAR FILM STABILIZATION

ADRIANA STANILĂ

“Lucian Blaga”University Sibiu, Ocular surface research center

Abstract: The dry eye syndrome is a multifactorial

condition of the tears and the ocular surface that causes

symptoms of ocular distress, afecting the sight, the lack of

balance of the lacrimal film with a distructive potential on

the eye surface. The clinical experience lead us to the

conclusion that there is a good correlation between the

severity of the dry eye syndrome and the presence and

intensity of the parallel conjunctival fold with the eyelid.

Assuring the lubrication of the cornean surface represents

the desideratum in the treatment of the dry eye and is an

important factor that we should take into account when

we choose the treatment.

Keywords: dry eye syndrome, lacrimal film, artificial

tears

Rezumat: Ochiul uscat este o afecţiune multi – factorială

a lacrimilor şi suprafeţei oculare ce determină simptome

de disconfort ocular, afectarea vederii şi instabilitatea

filmului lacrimal, cu potenţial distructiv asupra suprafeţei

oculare. Experienţa clinică a dus la concluzia că există o

bună corelare între severitatea sindromului de ochi uscat

şi prezenţa sau intensitatea pliurilor conjunctivale

paralele cu pleoapa. Asigurarea lubrifierii suprafeţei

corneene reprezintă un deziderat al tratamentului

ochiului uscat şi ca urmare, este un factor important de

care trebuie să ţinem cont în alegerea tratamentului.

Cuvinte cheie: ochi uscat, film lacrimal, lacrimi

artificiale

INTRODUCERE

Dry eye is a multifactorial disease of the tears

and ocular surface that results in symptoms of discomfort,

visual disturbance, and tear film instability, with potential

damage of the ocular surface. It is accompanied by

increased osmolarity of the tear film and inflammation of

the ocular surface (16).

The incidence of dry eye syndrome is on the

increase. Known risk factors, such as computer monitor

work, taking of certain pharmaceutical drugs, air-

conditioning systems and central heating indicate that it is

a typical civilization disease. The prevalence of dry eye

also increases with increasing age. The prevalence of dry

eye symptoms is reported to be 5-30 percent in adults

(2,3).

Etiological classification of the dry eye disease is

related to the tear film instability and hypo secretion.

Tear film instability can be determined either by a chronic

/ recurrent inflammation (allergy, blepharitis, rosacea,

environment, preservative, contact lenses and contact

lenses solutions, chalasis / lid margin irregularities), either

by acute aggressions (viral / bacterial conjunctivitis,

preservative, cataract / refractive surgery / Lasik). Hypo

secretion is determined by Sjögren’s Syndrome or other

autoimmune diseases, menopause, neurotrophic diseases

or different systemic drugs (antidepressants, beta-

blockers, antihistamines)

It can be assumed that the clinical picture of the

dry eye will be diagnosed even more frequently in future.

The diagnosis of the dry eye disease is based on

subjective symptoms, objective clinical signs and

diagnostic tests. There are several various clinical

diagnostic tests in use; however the correlations between

their results are week (1,2,3,4,5).

Clinical experience gave rise to the assumption

that there is a relation between the degree of severity of

the dry eye syndrome and the presence or the intensity of

the lid-parallel conjunctival folds (LIPCOF). This relation

was examined by Höh, Schirra, Kienecker and Ruprecht

and classified in the form of a grading scheme.

Lid-parallel conjunctival folds (LIPCOF) is a

non-invasive, simple diagnostic test for dry eye diseases

(6,7,8,9). During slit lamp examination it can be observed

the presence and degree of lid-parallel conjunctival folds

bordering the posterior lid margin as described by Höh et

al. (10,11).

Höh et al. (11) showed LIPCOF as a diagnostic

tool facilitates diagnosis of dry eye syndromes. Based on

their results it seems that LIPCOF is a sure sign of dry

eye: in 267 patients they found 75.95 % negative

predictive value and 93.09 % positive predictive value

(11). For comparison, a much used test in dry eye

diagnosis – TFBUT (tear film brake-up time), has a

72,2% positive predictive value (16). However, few

authors found only minor differences in LIPCOF signs

between moderate dry eye subjects and healthy persons

(12,13).

Höh et al also proposed that LIPCOF can be

reversed by intensive dry eye treatment (14). Dausch et al

(15) found that dry eye therapy improved significantly the

LIPCOF parameter and it can be useful in monitoring dry

eye treatments


AMT, vol II, nr. 1, 2010, pag. 82

Method of LIPCOF measurement and grading

LIPCOF can be found nasally, centrally and temporally

on both the upper and the lower eyelid. They border on

the posterior lid edge running parallel to it. Most

frequently, the LIPCOF appear inferiorly temporal. For

this reason, this quadrant of the palpebral fold is

examined with the slit lamp. The examination is

performed on the non-manipulated eye in primary

position.

The eye of the patient is in primary position

(patient looks straight ahead). The patient should have

some blinks. Then you can evaluate the LIPCOF stage as

Höh et al have described them at the lower lid margin in

the temporal lower quadrant without touching the eyelids.

The examiner looks for a horizontal conjunctival fold at

the transition from the middle to the temporal one-third of

the lower lid (10,11,14,15), with the slit lamp adjusted to

general observation magnification (10,11,14,15). The

degrees are according to the size of the conjunctival folds

as compared to the height of the normal tear meniscus

height and to the number of individual folds they

comprise. The lower limit value for the height of the

normal tear meniscus amounts to 0.2 mm.

Real LIPCOF's disappear, when you pull the

lower eye lid away from the eye. They form again after

some blinks and they always form in the same stage.

With Degree 0, no conjunctival fold exists. This

applies to the state of rest of the eye and does not exclude

that a conjunctival fold is pushed ahead of the lower

eyelid when the eye is being closed. No dry eye.

LIPCOF Degree 1 describes the permanent

presence of an individual fold, which does not exceed the

height of the normal tear meniscus. Mild intensity of dry

eye.

With Degree 2, because of a higher volume, the

LIPCOF disintegrates into two or several small parallel

folds, which however are lower than the normal tear

meniscus. Moderate intensity of dry eye.

If there are several, parallel conjunctival folds

exceeding the height of the normal tear meniscus,

LIPCOF Degree 3 exists. Severe intensity of dry eye.

Table no. 1. Summarizes the LIPCOF Degrees and

their interpretation.

It becomes much clearer that an essential part of

the dry eye syndrome management is the stabilization of

the tear film. This represents a major action in order to

increase TFBUT, corneal surface lubricity and the

retention time of the lubricant ophthalmic drops on the

corneal surface.

Figure no. 1. LIPCOF Degree 0 No permanently

present fold

Figure no. 2. LIPCOF Degree 1 Single, small fold;

smaller that the normal tear meniscus

Figure no. 3. LIPCOF Degree 2 Fold of up to the

height of the normal tear meniscus, multiple folds

Figure no. 4. LIPCOF Degree 3 Fold being higher

than the normal tear meniscus, multiple folds

The upper lid exerts significant pressure of 50 –

70 g (18) on the ocular surface and this force is normally

mitigated by the lubricity of the tear film. The average

pressure during blinking is 10,3 mmHg (19). In a normal

eye the lid exerts a smooth even pressure which sweeps

the eye, cleaning, surfacing and facilitating the normal

removal of dying corneal epithelial cells. In patients with

symptomatic ocular dryness, the upper lid exerts a

destructive force due to the increase in the coefficient of

friction. This results in an exposed ocular surface.

Lubrication between lid and ocular surface is an often

overlooked cause of discomfort and surface damage;

when lubricity decreases, the friction forces increase, and

this is the moment when we detect the LIPCOF signs.

This should be treated by tear substitute with low


AMT, vol II, nr. 1, 2010, pag. 83

coefficient of friction.

Many factors determine composition and

lubricity of the human tear film and its three layers

(aqueous, mucin, and lipid). Tear film needs to maintain

high lubricity across the ocular surface so that the lid

wiper can move across it smoothly. If friction is allowed

to build, the constant motion of the lid across the ocular

surface can cause discomfort.

But exactly how does a lower coefficient of

friction protect the lid and ocular surface? A laboratory

study assessed the intrinsic lubricity of SYSTANE® by

comparing the coefficient of friction (or the resistance to

movement) of earlier generation lubricating eye drops

(17). Tissue on tissue cultures representing the eyelid

were attached to hemispherical supports and friction was

assessed by measuring the speed and force at which the

resistance occurred. The results show that SYSTANE®

has over 6x greater lubricity than carbomethylcellulose;

nearly 4X greater lubricity than polysorbate 80 + glycerin

and over 2.5x greater lubricity than HPMC 0.03%. In a

clinical context, SYSTANE® uniquely restores lubricity

resulting in a decreased coefficient of friction between the

upper lid and the cornea. This is one of the key attributes

of SYSTANE® and explains its clinical efficacy in

reducing dry eye symptoms.

When in bottle, SYSTANE® looks like a normal

liquid eye drop. Applied to the corneal surface of a dry

eye patient, SYSTANE® forms a protective shield and

turns into a gel (in-eye gelling effect) with an action

similar to the one of the natural glicocalix. This protective

gel decreases evaporation; increases tear film stability,

lubricate and help in the initiation of the tissue repairing

processes. The increasing intensity of dry eye is directly

correlated to the increased pH of the ocular surface, and

SYSTANE® viscosity is directly correlated to the ocular

pH. So, as higher is the severity of the dry eye, as higher

is the gellifying action of SYSTANE®.

In conclusion, ensuring a correct lubrication of

the corneal surface represents the main goal of the dry eye

treatment and represents an important factor that has to be

taken into consideration when choosing the treatment.

SYSTANE® ensures the best lubricity compared to the

rest of the available artificial tears.

BIBLIOGRAFIE 1. Begley CG et al. IOVS 2003; 44: 4753-61

2. Brewitt H. , Sistani F.: Dry eye disease: the scale of the

problem Surv. of Ophthalm. 2001 March;45 (2):199-

202

3. Korb D.R., Craig J., Doughty M., Guillon J., Smith G.:

The tear film. Structure, function and clinical

examination. Butterworht-Heinemann,2002

4. Nichols KK, Mitchell GL, Zadnik K. The repeatability

of clinical measurrements of dry eye. Cornea.

2004;23:272-285.

5. Nichols KK, Nichols JJ, Mitschell GL. The lack of

association between signs and symptoms in patients

with dry eye disease. Cornea 2004;23:762-70.

6. Meller D, Tseng SCG: Conjunctivochalasis: literature

review and possible pathophysiology. Surv Ophthalmol

1998;43:225-232

7. Murube J: Characteristics and etiology of

conjunctivochalasis: historical perspective. The Ocular

Surface 2005;3:7-12

8. Schirra F, Hoh H, Kienecker C, Ruprecht KW: Using

LIPCOF (lid- parallel conjunctival fold) for assessing

the degree of dry eye, it is essential to observe the exact

position of that specific fold. Lacrimal gland, tear film

and dry eye syndrome 2, edited by Sullivan et al,

Plenum Press, New York, 1998

9. Yokoi N, Komuro A, Maruyama K, Tsuzuki M,

Miyajima S, Kinoshita S: New surgical treatment for

superior limbic keratoconjunctivitis and its association

with conjunctivochalasis. Am J Ophthalm 2003;

135:303-308

10. Höh H., Schirra F., Kienecker C., Ruprecht KW.: Lid-

parallel conjunctival folds are a sure diagnostic sign of

dry eye. Ophthalmologe 1995 Dec;92(6):802-8

11. Höh H, Schirra F, Kienecker C, Ruprecht KW: Lid-

parallel conjunctival fold (LIPCOF) and dry eye: a

diagnostic tool for the contactologist. Contactologia

1995(17): 104-117

12. Erdélyi B., Kraak R., Zhivov A., Guthoff R., Németh J.:

In vivo confocal laser scanning microscopy of the

cornea in dry eye. Graefe’s Arch Clin Exp Ophthal 2007

245: 39-44

13. Miller WL., Narayanan S., Jackson J., Bergmanson J.:

The association of bulbar conjunctival folds with other

clinical findings in normal and moderate dry eye

subjects. Optometry, 2003 Sep;74(9):576-82

14. Höh H., Schwanengel M.: Regression of lid –parallel

conjunctival folds (LIPCOF) on topicaltreatment with

Liposic Eye Gel: a pilot study. Klin. Monatsbl.

Augenheilkd, 2006 Nov; 223(11):918-23

15. Dausch D, Lee S., Dausch S., Kim JC., Schwert G.,

Michelson W.: Comparative study of treatment of dry

eye syndrome due to disturbances of the tear film lipid

layer with lipid containing tear substitutes. Klin.

Monatsbl. Augenheilkd. 2006 Dec; 223(12): 974-83

16. Lemp MA, Baudoin C, Baum J et al. The definition and

classification of dry eye disease: Report of the

Definition and Classification Subcommittee of the

International Dry Eye Workshop (2007). Ocular Surface

2007; 5:75-92

17. Paugh, JR, Meadows D, Christensen M. The residence

time of artificial tears in dry eye subjects. Paper

presented at: American Academy of Optometry Annual

Meeting; December 2005; San Diego, Calif. E-abstract

#050062 (US Study

18. Burton EW. Trans Am Ophthalmol Soc 1942; 40: 340

19. Miller D. Arch Ophthalmol 1967; 78: 328)


AMT, vol II, nr. 1, 2010, pag. 84

REASONS TO CHOOSE SILICONE HYDROGEL LENSES

CHRISTINA N. GRUPCHEVA

Medical University Varna, Bulgaria

Keywords: silicone hydrogel contact lenses

We are heading towards the end of the last

decade of the new Millennium. What happened for the

past 10 years in the contact lens world? In one word – a

revolution…

The old hydrogel material together with the old

concept for water content is a history. The new key word

is “silicone hydrogels”. This new word introduced

completely new terminology in relation to water content

and oxygen transmissibility. In the near past we believed

that more water means more comfort, however, on the top

of the recognized complications more water was

associated with more dryness and more discomfort. The

hydrogel materials have a property to “take” water from

the environment including hydrating chambers and the

tear film. Furthermore, when placed into the ocular

surface the lens changes the unique structure of the tear

film, dividing it into pre lens (lipid-water) and post lens

(water-mucin) layers. This will result in faster water

evaporation and lens dehydration. Then with high-water

content this will also close a vicious circle when lens will

dehydrate, and following it’s natural properties will take

the water from the tear film, which will change further it’s

structure and cause more evaporation…

To address those issues contact lens research and

technology invented two new products – silicone

hydrogels, and “water keeping” products. Silicone

hydrogel lenses appeared to be a completely new concept.

Firstly, in relation to oxygen transmissibility, there are

critical parameters (permability and thickness) after

certain value of which the oxygen can’t penetrate better.

At this value the oxygen concentration on both sides of

the lens is with the same value. Does it mean that such a

lens has no impact on the cornea after this critical value?

NO! The motivation for this answer is the concept of

oxygen flux and the mechanical properties of the lens.

Oxygen flux is the amount of oxygen required by a given

cornea at a particular moment, which means that to define

this value we shell look at many variables most of which

not measurable.

Oxygen Consumption Oxygen transmissibility (Dk/t) is the

measurement of how much oxygen passes through a lens

of given thickness in the air. To address the issue of

oxygen consumption a new measure – oxygen flux was

introduced into the clinical research and practice. Oxygen

flux is a measure of how much oxygen is available to the

cornea when the lens is on the eye.

However, these measures do not show how much

oxygen the corneal cells are metabolisingTotal corneal

oxygen consumption represents an index of corneal

oxygen metabolism and thus cellular energy production1.

The oxygen flux, therefore, is judged by indirect

clinical values as microcysts, microstriae, striae, corneal

oedema and corneal neovascularisation. Silicone hydrogel

lenses are providing extremely good transmissibility for

oxygen, however, oxygen flux requires individual clinical

judgment by the eye specialist. That is why all extended

wear patients require very tight schedule for follow

up.Oxygen deprivation impacts on all layers of the

cornea. The epithelium thins, the stroma develops striae,

the endothelium shows blebs and polymegethism, the

conjunctival vessels dilate leading to hyperaemia. As

health care professionals surely we should seek to

minimise these effects.

Oxygen Consumption Maps The newer concept introduced by Noel Brennan,

is the concept of percentage oxygen consumption. In this

model, the actual amount of oxygen needed to ensure

completely normal cellular activity underneath every part

of the CL is calculated. In the case of the natural eye,

every cell in the cornea will receive all the oxygen it

needs to metabolise normally. This is also the case with 1

DAY ACUVUE® TruEye™, irrespective of lens power

(higher minus lenses are thicker reducing potential

oxygen delivery). Oxygen consumption across the entire

cornea is not affected by the wearing of 1·DAY

ACUVUE® TruEye™ irrespective of power.

The other problem is based on mechanical

properties of the silicone-hydrogel lenses. There are many

parameters most important of which are modulus,

wettability, lubricity, dehydration, deposits, edge design

and thickness. Unfortunately the design is not an

universal property, as anterior ocular surface varies

between subjects. Selection of a certain design is more or

less empirical and is based on clinical performance and

subjective appreciation of a given lens.

If the eye specialist wants to utilize SiH lenses,


AMT, vol II, nr. 1, 2010, pag. 85

they must follow few simple rules as follows:

- Examine & listen to your patients with contact lens

related dryness

- Ask patients about the number of hours of

comfortable lens wear vs. total hours

- Be careful about patients reports regarding napping

- Pay special attention to patients working on a

computer

- Remember: Contemporary tendency is lens wearers

to be older, use more medications, spend more time

in front of monitors and in air conditioned

environment than in the past.

The contact lens world is changing very fast. The

information via internet is instantaneous. All this

globalization should impact contact lens habits. Before

expecting our patients to change, we should change our

minds, our fitting habits and our contact lens practices.

BIBLIOGRAPHY

1. Brennan NA. Beyond flux: Total corneal oxygen

consumption as an index of corneal oxygenation

during contact lens wear. Optometry and Vision

Science 2005; 82(6): 467-472)

Courtesy of Brennan NA and Johnson and Johnson


AMT, vol II, nr. 1, 2010, pag. 86

CORNEAL STAINING: DO WE UNDERSTAND WHAT WE

ARE SEEING?

SILVIA BELCHEVA1, CHRISTINA N GRUPCHEVA2

1Private Practice, Bulgaria, 2Medical University Varna, Bulgaria

Keywords: corneal staining, fluorescein, staining in

contact lens wearers

Sodium fluorescein (‘fluorescein’) is widely

utilised for the evaluation of ocular surface integrity. It is

preferred for anterior ocular surface visualisation due to

its fluorescent properties and its high visibility at low

concentrations. Ocular surface fluorescence observed

clinically is affected by a number of factors including

concentration of fluorescein, thickness of the fluorescein

layer, the wavelength of the exciting light source and

whether or not a barrier filter is used as part of the

viewing system. Three potential cellular mechanisms are

involved in corneal surface fluorescence: surface pooling,

uptake by cells and ingress around cells. Despite the

widespread adoption of use of fluorescein for the

assessment of the ocular surface, the clinical

understanding and interpretation of corneal surface

fluorescence is based upon clinical intuition rather than

underpinning the basic causative mechanisms of this

phenomenon, particularly important for contact lens

wearers.

It is important to understand and to interpret the

corneal staining in all cases of adaptation of contact

lenses, including silicone hydrogel lenses. It demonstrates

chronic injury of the corneal epithelium. The intact

epithelium is the best protection against corneal invasion.

Corneal staining means “clinical procedure allowing the

observation of the vitality and integrity of the corneal

epithelium cells using dye (fluorescein)”. The observation

of the corneal surface with the blue filter of the slit lamp

after instillation of fluorescein allows visualisation of

lesions with different localisation and importance.

What is the value of staining in contact lens wearers

and non wearers?

According to different clinical studies the

corneal staining observed in patients non wearing contact

lenses varies between 4 to 79% depending on the method.

It is usually under first grade or if it is of first grade, is

situated in the half of the cases in the inferior area of the

cornea. It is a result of the impaired tear film. In 30 to

50% of contact lens wearers the staining is under second

grade and in 5 to 10 % of them – above second grade.

Corneal staining is usually asymptomatic, but must be a

part of the routine contact lens examination.

Description and quantitative assessment of corneal

staining The description is according:

Depth: superficial and deep;

Localisation: the cornea is divided into five areas:

central, superior, inferior, nasal and temporal.

Corneal staining grades grade 0 = no staining,

grade 1 = micropunctate staining, clinically

insignificant,

grade 2 = macropunctate staining, it must be noted

and followed up,

grade 3 = moderate coalescent macropunctate

staining, requires treatment,

grade 4 = marked patch staining, requires immediate

treatment.

The visual acuity is usually unaffected except for

the central form of grade 4.

Corneal staining Grading Scales, most widely used


AMT, vol II, nr. 1, 2010, pag. 87

Clinical forms of corneal staining

Punctate corneal staining: tiny superficial dots –

keratitis punctata superficialis.

Localised or diffuse staining of the cornea with

coalescent dots.

Staining at 3 and 9 o’clock, classical form of staining

induced by hard contact lenses. A temporal and nasal

staining is observed; the reason is the slow renewal of

the tear film between two blinking.

Staining like “smile”: arched epithelial staining

inferiorly between 4 and 8 o’clock, observed in soft

contact lens wearers. It is related with instable tear

layer between the lens and the cornea. It is observed

in 3,3% of soft contact lens wearers.

Superior arcuate epithelial lesion

This is frequent and asymptomatic complication

of silicone hydrogel contact lenses. It is situated in the

superior area of the cornea, covered by the upper eyelid at

2-3 mm of the limbus between 10 and 2 o’clock.The

silicone hydrogel lenses must be replaced with lenses with

lower modulus.

Diffuse staining

Peripheral staining

Inferior and superior staining

Limbal transition pooling

Etiology

There are six known etiologies: mechanical,

expositional, metabolite, infectious, toxic and allergic.

However ,in many cases the reason remains unknown.

Mechanical factors

Defective lens, badly adapted (especially rigid

lens) or badly maintained with deposits on its back

surface, foreign body under the lens and other causes for

microtrauma of the corneal epithelium.

Expositional factors

Typically it reveals like an arcuate lesion (like

smile) in the inferior third of the cornea and it is due to

exposure of the corneal epithelium which causes

dessication of epithelial cells. It is also observed in cases

of upper decentration of rigid lens with diminished

efficacy of blinking. Dry keratitis, related to dehydration

of the lens, could be observed in wearing high hydrophilic

soft contact lens. The staining presents with central

localisation. The staining at 3 and 9 o’clock is related

with this etiology as well.

Metabolic factors

The wearing of soft contact lens could induce

hypoxia followed by synthesis of lactic acid. This chronic

metabolic stress leads to damage of deep cells of corneal

epithelium with formation of microcysts. They produce

superficial diffuse and always bilateral staining. The

silicon hydrogel material allows to limit the hypoxia and

consequently to reduce these metabolic problems.

Infectious origin

A small corneal ulcer is usually observed

(foreign body under the lens, inappropriate night wear),

accompanied by corneal pain. The fluorescence is limited

in the area of the lesion, but characteristic sign is the

diffuse spread in the depth of stroma – posterior halo.

Toxic and/or allergic etiology

Superficial keratitis, related to toxic and allergic

reactions to components of maintaining products, are

observed. The improvement of maintaining systems (lack

of polyhexamethilen biguanide, РНМВ, tiomersal,

benzalkonium chloride, hexidine) should lead to

disappearance of punctate lesions of the cornea.

Is there a relation between corneal staining and

bacterial keratitis?

Obviously, the breaking of the epithelial barrier

of the cornea is “an open door” for infection, allowing

adhesion and later penetration.

By now the causative relation is not clearly proved.

The role of multipurpose solutions for appearing of

infections is not fully elucidated but it is always

strongly recommended the use of products with

minimal deleterious potential.

Conclusions

Corneal staining is a “must” evaluation for a good

contact lens practice.

Grading scales must be used to unify the findings and

examination repeatability.

Staining should be interpreted into the clinical

context.

Further corneal/contact lens solution interactions

should be elucidated.


AMT, vol II, nr. 1, 2010, pag. 88

LOWER BLEPHARPOPLASTY: CONTOURING IN A

SAFE APPROACH

STEFAN GRESS

Consultant Plastic Surgeon, Munich, Germany

INTRODUCTION

Effective lower blepharoplasty is a challenging

procedure that requires fundamental knowledge on

anatomical structures of the orbital and periorbital region

as well as surgical finesse and experience in facial plastic

surgery. The fear of potential complications and pitfalls,

e.g. postoperative ectropion, leads to inadequate approach

to the problems present especially by young and less

experienced surgeons.

This paper gives a guideline for a safe and

effective technique to contour or reconstruct the lower

eyelid.

MATERIAL AND METHOD

Between 2004 and 2008 we have performed 285

lower blepharoplasties for aesthetic and reconstructive

indications.

Aesthetic lower blepharoplasty was indicated to

treat relaxation and redundancy of the lower eyelid skin,

tear troughs or festoons, reconstructive indications

included any malpositioning of the lower eyelid such as

scleral show or ectropion for various reasons, e.g. trauma

or following aesthetic surgery.

The routine technique utilized was a combination

of techniques described by different authors, such as the

inferior retinacular lateral canthoplsty (G. Jelks) (1,2,3),

the arcus marginalis release (S.Hamra) (7) and periorbital

lipostructure (S. Coleman) (5,6).

Pre Op Management

Routinely surgery was carried out in general

anaesthetics as an outpatient procedure. For skin incision

and coagulation we used a Radio Frequency Device (25

watt) and for illumination of the infraorbital rim a 300

watt xenon light source and a nasal light hook retractor. A

cornea protection lens should be inserted. The infraorbital

region was infiltrated with xylocaine 1% with epinephrine

1:100000. Antibiotics (cephalosporine) was routinely

given for four days.

Surgical technique

Access to the lower eyelid is carried out via a

subciliar incision extended laterally when skin resection is

required (Fig1). A transconjunctival approach is an option

only if no skin redundancy is to be treated.

After infiltrating the lower lid with 1% xylocaine

and epinephrine (1:100000) the skin is separated from the

muscle in a small strip along the pretarsal portion of the

lower eyelid. A small muscle flap then is raised from the

lateral portion of the preseptal orbicularis oculi muscle

pedicled medially (Fig 2).

Figure no. 1. Subciliar incision

Figure no. 2. Medially pedicled preseptal orbicularis

muscle flap

Further dissection is carried out directly

supraperiostally along the infraorbital rim all along the

way to the medial insertion of the orbicularis oculi

muscle. A light hook retractor is inserted to facilitate the

view (Fig 3). The entire inferior orbital rim is exposed

(Fig.4). Preparation can be carried out by scissors or by a

raspatorium. From medially to laterally the orbital septum

is incised close to its insertion to the infraorbital rim

(arcus marginalis release). First the nasal and medial

orbital fat is gently pushed inferior over the orbital rim. It

is placed beneath the nasal insertion of the orbicularis

oculi muscle. The orbital fat is secured by two percutane

stitches (4-0 Prolene) to prevent the fat from sliding back

into the orbit (Fig 5,6,7). To avoid skin damage by the

sutures, the nodes should be placed above a small piece of

gauzes (Fig.8). The stitches are removed after four days.


AMT, vol II, nr. 1, 2010, pag. 89

Figure no. 3. Light hook retractor

Figure no. 4. Exposure of the inferior orbital rim

Figure no. 5. Orbital fat placed over the orbital rim

Figure no. 6 Orbital fat fixed by suture

If the amount of orbital fat is not sufficient to

create a nice contour of the lower eyelid or when the

orbital rim can not entirely be covered by orbital fat,

additional fat grafting can be performed (lipostructure).

The fat can be infiltrated from the subciliary approach or

percutaneously by a sharp or blunt needle (Fig 9).

However it should be placed above the periosteum and

not above the muscle. Overcorrection should be avoided.

The free fat grafts can be used to shape the entire cheek or

midface whenever volume replacement is necessary.

The lateral infraorbital fat pad, when pushed

over the orbital rim, is fixed by 5-0 Vicryl stitches.

Figure no. 7. Percutane fixation of the transpositioned

orbital fat

Figure no. 8. Knod placed over gauzes

Figure no. 9. Percutane fat injection

Prior to skin resection, the lower eyelid needs to

be secured and supported to avoid postoperative ectropion

or scleral show. We utilize the technique of Glenn Jelks,

the inferior retinacular lateral canthoplasty, which is

more a canthopexy procedure:

The superificial lamella of the lateral canthal

tendon is released at its lateral insertion to the orbital rim.

The dissection in continued inferiorly in a subperiostal

plane until it joins the lateral- inferior edge of the orbit

(that now is covered by the inferior lateral orbital fat pad).

Fibrous attachments that run from the lateral canthus into

the lateral inferior orbit are released to achieve free

movement of the lower lid. The lower lid component of

the lateral retinaculum (the component of the anterior

lamella of the lateral canthal tendon that forms the roof

the inferior lateral fat pocket) now is grasped and fixed

vertically into the inner aspect of the supero-lateral orbital

rim by a 5-0 Prolene suture (Fig 10,11). The elevation of

the lower eyelid should appear slightly overcorrected.

When canthoplasty is performed, the muscle flap

raised at the beginning of the procedure is now fixed

under moderate tension in an oblique superior direction to

the periosteum of the lateral orbital rim by 5-0 Vicryl (Fig


AMT, vol II, nr. 1, 2010, pag. 90

12) sutures. Before skin removal, muscle incisions are

closed by 5-0 Vicryl stiches.

Figure no. 10. Suture passing through the lateral

inferior retinaculum

Figure no. 11. Fixation of the lower lateral

retinaculum to the supero-lateral orbital rim

Figure no. 12. Fixation of the muscle flap to the lateral

orbit

Excess skin can safely be removed now. This

should be performed on open eyes to avoid overresection

(Fig 13). For skin closure 6-0 Prolene is used.

A steri-strip dressing is applied using an

additional long strip laterally to release tension of the

cheek on the incision (Fig 14).

Figure no. 13. Measuring skin excess prior to removal

Post Op management

Stitches are removed after four days, however

the steri- strip dressing should be continued 10- 14 days

following surgery. Any tension on the cheek and lower

eyelid should strictly be avoided for four weeks and the

patient should sleep on his back during that period of

time. We routinely give cephalosporine antibiotics for

four to five days

Figure no. 14. Steri strip dressing

Complications

The most common postoperative problem

encountered is chemosis to various degrees. Chemosis is

not treated actively, local steroids do not help

significantly (Fig 15).

Figure no. 15. Severe chemosis with haemorrage

Overresection of skin and hypertrophic scar

formation can lead to malpositioning of the lower eyelid,

e.g. to a round eye deformation, scleral show or ectropion.

This is seldomly seen when the procedure is performed

correctly and skin closure is carried out without tension.

In some cases granulomas can occur around the

permanent 5-0 Prolene suture that fixes the canthopexy. If

these reactions lead to irritations of the globe or the

patient feels uncomfortable, the suture can be removed

after four weeks.

RESULTS

Figure no. 16. 35 year old patient after lower lid

contouring. Additional lipostructure of the cheek and

midface was performed


AMT, vol II, nr. 1, 2010, pag. 91

Figure no. 17. 75 year old patient following upper and

lower blepharoplasty

Figure no. 18. 42 year old patient after contouring the

lower eyelid and lipostructure of the nasojugual groofe


lower eyelid and upper blepharoplasty


left lower lid malpositioning following a blow out

fracture

CONCLUSION

For contouring the lower eyelid, the combination

of reshaping inferior orbital fat, fat grafting and muscle

and skin tightening are all together effective tools to

achieve functionally and aesthetically pleasing results in

lower blepharoplasty. To prevent pitfalls and

complications such as postoperative ectropion, a safe

support of the lower eyelid is mandatory. Therefore we

routinely utilize the inferior retinacular lateral

canthoplasty, described by Glenn Jelks. We also utilize

the “no touch technique” that does not allow complete

transsection of the orbicularis oculi muscle along the

lower eyelid for better access to the orbit, because it

would lead to denervation of the pretarsal portion of the

orbicularis oculi muscle likely emerging into a round eye

deformity.

When the guidelines presented in this paper are

perfomed correctly, the lower blepharoplasty will be

successful.

REFERENCES

1. Jelks, G.W. The Inferior Retinacular Lateral

Canthoplasty: A New Technique. Plast. Reconstr.

Surg. 100:1262,1997

2. Jelks, G.W., and Jelks, E.B. Repair of lower lid

deformities. Clin. Plast. Surg. 20: 417, 1993

3. Zide, B.M, and Jelks, G.W. Surgical Anatomy of the

Orbit. New York: Raven Press, 1985

4. Muzaffar, A.R., Mendelson, B.C. Surgical Anatomy

of the Ligamentous Attachments of the Lower Lid

and Lateral Canthus. Plast. Reconstr. Surg. 110: 873,

2001

5. Coleman, S.R., Guerrerosantos, J. Volumetric

Considerations in Facial Augmentation. Journal for

Aesthetic Surgery, 2: 2003

6. Coleman, S.R., Facial recontouring with

lipostructure. Clin. Plast. Surg. 24(2): 347, 1997

7. Hamra, S.T., The role of septal reset in creating a

youthful eyelid- cheek complex in facial

rejuvenation. Plast.Reconstr. Surg., 113 (7): 2124,

2004

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